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Sample records for chest x-ray findings

  1. Chest X Ray?

    Science.gov (United States)

    ... this page from the NHLBI on Twitter. Chest X Ray A chest x ray is a fast and painless imaging test ... tissue scarring, called fibrosis. Doctors may use chest x rays to see how well certain treatments are ...

  2. Chest X-Ray

    Medline Plus

    Full Text Available ... breath, persistent cough, fever, chest pain or injury. It may also be useful to help diagnose and ... have some concerns about chest x-rays. However, it’s important to consider the likelihood of benefit to ...

  3. Radiological findings in megaesophagus secondary to Chagas disease: chest X-ray and esophagogram*

    Science.gov (United States)

    Abud, Thiago Giansante; Abud, Lucas Giansante; Vilar, Vanessa Sales; Szejnfeld, Denis; Reibscheid, Samuel

    2016-01-01

    Objective To identify and classify the radiographic patterns of megaesophagus in Chagas disease, as seen on esophagograms and chest X-rays. Materials and Methods This was a prospective study of 35 patients diagnosed with esophageal disease via manometry. The changes found on esophagograms were stratified according to Rezende's classification, divided into four categories (grades I through IV) determined by the degree of dilatation and impairement of esophageal motility. We subsequently correlated that ranking with the chest X-ray findings: gastric air bubble; air-fluid level; and mediastinal widening. Results Among the 35 patients, the esophageal disease was classified as grade I in 9 (25.7%), grade II in 3 (8.6%), grade III in 19 (54.3%), and grade IV in 4 (11.4%). None of the patients with grade I esophageal disease showed changes on chest X-rays. In two of the three patients with grade II disease, there was no gastric air-bubble, although there were no other findings in any of the grade II patients. Of the 19 patients with grade III disease, 15 had abnormal findings on X-rays. All four patients with grade IV disease showed abnormalities. Conclusion The use of Rezende's classification is feasible, encompassing findings ranging from the subtle changes that characterize the initial phases of esophageal disease to the complete akinesia seen in dolicomegaesophagus. Chest X-ray findings are more common in patients with advanced stages of the disease and indicate the degree of esophageal involvement in Chagas disease. PMID:28100930

  4. Endoscopics findings in patients with hemoptysis and normal chest X-ray

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    Sandra Beltrán Labaut

    2012-02-01

    Full Text Available Hemoptysis is defined as the outcomming of blood from the subglotic region, habitually by the mechanism of cough. A cross- sectional, retrospective, transverse and descriptive study was carried out in patients with hemoptysis and normal PA thorax's x-ray. To whom were practiced bronchoscopy in the "Benéfico Jurídico" Neumologyc Hospital from January 1999, to January 2009, with the purpose of identifing the endoscopyc discoveries obtained through this procedure. The information was obtained from the bronchoscopy, microbiology and pathological Anatomy records of this center. The population was composed by 197 sick people and the sample was constituted by 67 patients. The statistical analysis was carried out in the program EPIDAT version 3.0. Mediates and standard (SD were used for quantitative variables and absolute frequency and the percentages with their respective intervals of trust of 95% were used in all the variables. The masculine sex prevailed with a total of 45 patients (67.2% and the age group was among 40-49 years old. In 70.1% of the cases it was observed inflammatory signs, and it was also obtained growth of pathogenics germs in 16 patients and in 17 (25.3% it was confirmed the diagnosis of neoplasic desease by biopsy and/or bronchial brushing.

  5. Tuberculosis, advanced - chest x-rays (image)

    Science.gov (United States)

    Tuberculosis is an infectious disease that causes inflammation, the formation of tubercules and other growths within tissue, ... death. These chest x-rays show advanced pulmonary tuberculosis. There are multiple light areas (opacities) of varying ...

  6. Inter-rater agreement in the assessment of abnormal chest X-ray findings for tuberculosis between two Asian countries

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    Sakurada Shinsaku

    2012-02-01

    Full Text Available Abstract Background Inter-rater agreement in the interpretation of chest X-ray (CXR films is crucial for clinical and epidemiological studies of tuberculosis. We compared the readings of CXR films used for a survey of tuberculosis between raters from two Asian countries. Methods Of the 11,624 people enrolled in a prevalence survey in Hanoi, Viet Nam, in 2003, we studied 258 individuals whose CXR films did not exclude the possibility of active tuberculosis. Follow-up films obtained from accessible individuals in 2006 were also analyzed. Two Japanese and two Vietnamese raters read the CXR films based on a coding system proposed by Den Boon et al. and another system newly developed in this study. Inter-rater agreement was evaluated by kappa statistics. Marginal homogeneity was evaluated by the generalized estimating equation (GEE. Results CXR findings suspected of tuberculosis differed between the four raters. The frequencies of infiltrates and fibrosis/scarring detected on the films significantly differed between the raters from the two countries (P P = 0.0082, respectively, by GEE. The definition of findings such as primary cavity, used in the coding systems also affected the degree of agreement. Conclusions CXR findings were inconsistent between the raters with different backgrounds. High inter-rater agreement is a component necessary for an optimal CXR coding system, particularly in international studies. An analysis of reading results and a thorough discussion to achieve a consensus would be necessary to achieve further consistency and high quality of reading.

  7. Impact of positive chest X-ray findings and blood cultures on adverse outcomes following hospitalized pneumococcal lower respiratory tract infection

    DEFF Research Database (Denmark)

    Skovgaard, Marlene; Schønheyder, Henrik Carl; Benfield, Thomas;

    2013-01-01

    Little is known about the clinical presentation and outcome of pneumococcal lower respiratory tract infection (LRTI) without positive chest X-ray findings and blood cultures. We investigated the prognostic impact of a pulmonary infiltrate and bacteraemia on the clinical course of hospitalized...

  8. Senile Calcification of the Trachea, Aortic Arch, and Mitral Annulus: An Incidental Finding on Chest X-Ray.

    Science.gov (United States)

    Hosseinzadeh Maleki, Mahmood; Kazemi, Toba; Davoody, Navid

    2015-10-27

    A 94-year-old woman presented with dizziness and hypotension of 2 days' duration. She denied any syncope, presyncope, or angina. She had received a permanent pacemaker 12 years previously for the management of complete heart block (CHB), but she failed to program it. Twelve-lead electrocardiography revealed CHB with ventricular escape rhythm (40/min), so we inserted a temporary pacemaker. Anteroposterior chest X-ray showed trachea, aortic arch, and severe mitral valve calcification. Tracheal calcification is usually seen after 40 years old without clinical importance. However, it is seen in patients with renal failure, metastases, and prolonged use of warfarin as well as in pregnancy.(1) (-) (3).

  9. 20 CFR 718.102 - Chest roentgenograms (X-rays).

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Chest roentgenograms (X-rays). 718.102... roentgenograms (X-rays). (a) A chest roentgenogram (X-ray) shall be of suitable quality for proper classification...-rays as described in Appendix A. (b) A chest X-ray to establish the existence of pneumoconiosis...

  10. Giant pericardial cyst mimicking dextrocardia on chest X-ray.

    Science.gov (United States)

    Hamad, Hamad M; Galrinho, Ana; Abreu, João; Valente, Bruno; Bakero, Luis; Ferreira, Rui C

    2013-01-01

    Pericardial cysts are rare benign congenital malformations, usually small, asymptomatic and detected incidentally on chest X-ray as a mass located in the right costophrenic angle. Giant pericardial cysts are very uncommon and produce symptoms by compressing adjacent structures. In this report, the authors present a case of a symptomatic giant pericardial cyst incorrectly diagnosed as dextrocardia on chest X-ray.

  11. Poor interpretation of chest X-rays by junior doctors

    DEFF Research Database (Denmark)

    Christiansen, Janus Mølgaard; Gerke, Oke; Karstoft, Jens;

    2014-01-01

    INTRODUCTION: Studies targeting medical students and junior doctors have shown that their radiological skills are insufficient. Despite the widespread use of chest X-ray; however, a study of Danish junior doctors' skills has not previously been performed. MATERIAL AND METHODS: A total of 22...... diagnosis, the participant's confidence in the diagnosis was assessed on a five-point Likert scale. The diagnoses were divided into four groups: normal findings, chronic diseases, acute diseases and hyperacute diseases or conditions. RESULTS: A total of 22 doctors receiving basic clinical education (BCE...

  12. Chest X-ray imaging of patients with SARS

    Institute of Scientific and Technical Information of China (English)

    陆普选; 周伯平; 陈心春; 袁明远; 龚小龙; 杨根东; 刘锦清; 袁本通; 郑广平; 杨桂林; 王火生

    2003-01-01

    Objective To investigate the chest X-ray manifestations of SARS cases.Methods A retrospective study was conducted among 52 clinically confirmed SARS patients from February 9 to May 10, 2003. Chest X-ray scanning was performed at a interval of 1-3 days according to the requirements. The manifestations and special features of SARS in X-ray were analyzed. Results Small or large patchy shadows with intensive density in both lungs were observed in 31 cases, ground-glass like opacification in 16, small patchy shadows in one lung lobe or one lung segment in 18, nodular shadows in one lung segment in 1, and increased lung marking in lung interstitial tissues in 2. Rapidly changing consolidations revealed in chest X-ray images were found to be associated with SARS infections, and they were not affected by treatment with antibiotics.Conclusion Chest X-ray provides a sensitive and specific method for the diagnosis and treatment of SARS, and those present with symptoms and signs should undergo chest X-ray scanning every 1-3 days.

  13. Risks of Chest X-ray Examination for Students

    Directory of Open Access Journals (Sweden)

    Nohara,Takahiko

    2009-02-01

    Full Text Available

    Chest X-ray (CXR examination is considered essential for health checkups of students;thus, it is important to objectively assess the CXR for a better understanding of the appropriate X-ray exposure dose, and the risks such an examination entails. Accordingly, we performed a multi-institutional study regarding students' CXR exposure, during a 6year-period from 2002 (partially including 2001 to 2007, with the collaboration of national, municipal, and private universities and colleges in Japan. A glass badge was worn by the students at the time of CXR screening examination. These glass badges were collected, and their X-ray exposure doses were measured. The results indicated a tendency of decreasing exposure dose over the 6 years, though the difference was not significant. In a comparison of the chest X-ray systems within institutions (own X-ray equipmentinside systems with those outside the institution (mobile X-ray equipmentoutside systems, the average exposure dose with the outside systems exceeded that of the inside systems. Both inside and outside systems included a few X-ray machines with which the exposure was more than 1mSv. Based on these facts, individuals in charge of student health checkups should be aware of the exposure dose of each chest fluorographic system at their institution.

  14. Image processing system for digital chest X-ray images

    Energy Technology Data Exchange (ETDEWEB)

    Cocklin, M.; Gourlay, A.; Jackson, P.; Kaye, G.; Miessler, M. (I.B.M. U.K. Scientific Centre, Winchester (UK)); Kerr, I.; Lams, P. (Radiology Department, Brompton Hospital, London (UK))

    1984-01-01

    This paper investigates the requirements for image processing of digital chest X-ray images. These images are conventionally recorded on film and are characterised by large size, wide dynamic range and high resolution. X-ray detection systems are now becoming available for capturing these images directly in photoelectronic-digital form. The hardware and software facilities required for handling these images are described. These facilities include high resolution digital image displays, programmable video look up tables, image stores for image capture and processing and a full range of software tools for image manipulation. Examples are given of the applications of digital image processing techniques to this class of image.

  15. Annual Screening with Chest X-Ray Does Not Reduce Lung Cancer Deaths

    Science.gov (United States)

    Annual screening for lung cancer using a standard chest x-ray does not reduce the risk of dying from lung cancer when compared with no annual screening, according to findings from the NCI-led Prostate, Lung, Colorectal, and Ovarian (PLCO) screening trial.

  16. Diagnostic modalities x-ray and CT chest differ in the management of thoracic injury

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    D Chapagain

    2015-06-01

    Full Text Available Objective: To observe difference in the management of blunt trauma to the chest on the basis of conventional xray and computerised tomography of the chest. Methods: This prospective study was conducted between December 2011 to October 2012 in COMS in Bharatpur,a tertiary referral centre in central Nepal . Clinically stable thoracic injury patients were first evaluated with chest x-ray and the management on this basis was recorded. The findings of the CT chest were assessed and the type of management on the basis of CT was also recorded. Outcome was assessed in terms of mortality, morbidity, hospital and ICU stay with respect to the management on the basis of chest x-ray and CT scan. Results: Of the 129 patients, 74.4% were male and 25.6% were female with the patients ranging in age from 7 to 87 years (mean = 40.41 years. The most common mechanism of trauma to the chest was as a result of a motor vehicle accident (69.8%, followed by fall injury (20.2%. X-ray chest diagnosed rib fracture in 62%, haemothorax in 37%, pneumothorax in 27%, lung contusion in 10% and haemopneumothorax in 21% patients. Similarly CT chest diagnosed rib fracture in 86%, haemothorax in 54%, pneumothorax in 36%, lung contusion in 30% and haemopneumothorax in 30% patients. Mean hospital stay was 9.5 days in the group of patients having management on the basis of x-ray chest relative to mean stay of 10.2 days in the CT- chest group. In the management on the basis of xray group, there was a mean ICU stay of 2.8days compared to mean stays of 3.2 days in CT chest group. Conclusion: Though CT scan of the chest is more informative and differs the management of the blunt chest trauma, one should not forget to advise the cost effective, easily available and initial guiding agent, xray chest for early management of the chest injury patient. DOI: http://dx.doi.org/10.3126/jcmsn.v10i1.12764 Journal of College of Medical Sciences-Nepal, 2014, Vol.10(1; 22-31

  17. Utility of chest X-ray and abdominal ultrasound for stage III cutaneous malignant melanoma

    DEFF Research Database (Denmark)

    Breitenbauch, M. T. W.; Holm, J.; Rødgaard, J. C.;

    2015-01-01

    . Patients were identified by procedure codes and cross-checked with the Danish National Pathology Database. Results: Ninety patients were included. All patients had chest X-ray and abdominal ultrasound performed. Five chest X-rays raised suspicion of lung metastases and four ultrasounds of liver metastases....... One patient had pleural metastases. Additional imaging and biopsies ruled out metastases in eight of nine cases. Eighty patients had normal imaging, and among these, two had metastases in the lungs and two in the liver at 1-year follow-up. For chest X-ray and abdominal ultrasound, sensitivity...

  18. Tuberculosis contact investigation using interferon-gamma release assay with chest x-ray and computed tomography.

    Science.gov (United States)

    Fujikawa, Akira; Fujii, Tatsuya; Mimura, Satoshi; Takahashi, Ryota; Sakai, Masao; Suzuki, Shinya; Kyoto, Yukishige; Uwabe, Yasuhide; Maeda, Shinji; Mori, Toru

    2014-01-01

    Between September 2009 and January 2010, 6 members of the Japanese Eastern Army, who had completed the same training program, were diagnosed with active tuberculosis (TB) on different occasions. The Ministry of Defense conducted a contact investigation of all members who had come into contact with the infected members. The purpose of this study was to verify the efficacy of the TB screening protocol used in this investigation. A total of 884 subjects underwent interferon-gamma release assay (IGRA) and chest X-ray. The 132 subjects who were IGRA positive or with X-ray findings suggestive of TB subsequently underwent chest computer tomography (CT). Chest CT was performed for 132 subjects. Based on CT findings, 24 (2.7%) subjects were classified into the active TB group, 107 (12.1%) into the latent tuberculosis infection (LTBI) group, and 753 (85.2%) into the non-TB group. The first 2 groups underwent anti-TB therapy, and all 3 groups were followed for 2 years after treatment. Although one subject in the active TB group experienced relapse during the follow-up period, no patient in the LTBI or non-TB groups developed TB. IGRA and chest X-ray, followed by chest CT for those IGRA positive or with suspicious X-ray findings, appears to be an effective means of TB contact screening and infection prevention.

  19. 20 percent lower lung cancer mortality with low-dose CT vs chest X-ray

    Science.gov (United States)

    Scientists have found a 20 percent reduction in deaths from lung cancer among current or former heavy smokers who were screened with low-dose helical computed tomography (CT) versus those screened by chest X-ray.

  20. Chest X-ray in newborns and infants; Konventionelle Thoraxdiagnostik bei Neugeborenen und Kleinkindern

    Energy Technology Data Exchange (ETDEWEB)

    Moritz, Joerg D. [Universitaetsklinikum Schleswig-Holstein, Kiel (Germany). Klinik fuer diagnostische Radiologie, Paediatrische Radiologie und Sonographie

    2012-12-15

    Chest X-ray in newborns and infants shows great differences to that in adults. Therefore all radiologists, who engage in X-rays in this age group, must be familiar with the special features. At the beginning specific items of examination methods are explained, which must be strictly followed due to radiological protection. Focus of the paper is the discussion of the important chest diseases in newborn and infants, which are mostly unknown in chest diagnosis in adults. Many of them can be life-threatening, thus their knowledge is essential. Pathophysiological explanations shall make the special radiological signs understandable. (orig.)

  1. Examination of funnel chests by X-ray and nuclear magnetic resonance tomography: First results and experiences

    Energy Technology Data Exchange (ETDEWEB)

    Raithel, H.J.; Hartung, M.; Gruennewig, B.; Willital, G.

    1983-01-01

    Funnel chest (pectus excavatum) is a congenital malformation of the thorax. Operative correction must presently be regarded as the treatment of choise. In addition to cosmetical and psychological reasons, there are mainly functional aspects justifying a surgery. The indication for surgery results mostly from the objective clinical-diagnostical findings. This article describes the efficiency of both X-ray computerized tomography and also nuclear magnetic resonance tomography (NMR-CAT) which has only recently been introduced to clinical diagnostics.

  2. Retroflexed holoprosencephaly. X-ray CT findings and MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Nagano, N.; Ohno, K.; Masaoka, H.; Fukai, N.; Matsushima, Y.

    1987-02-01

    We report a case of holoprosencephaly with retroflexion and discuss the usefulness of X-ray CT in its diagnosis. A 2-month-old infant, admitted with severe hydrocephalus, underwent a ventriculo-peritoneal shunt. The brain was retroflexed with subdural fluid collection after the procedure. The pathological condition was, however, gradually improved by the use of an additional subduro-peritoneal shunt. The shift and distortion of the brain were observed by means of serial X-ray CT scans. MRI revealed the brain stuck mainly to the frontal bone, monoventricle, the so-called dorsal sac, and probably the pituitary gland, but not the fourth ventricle nor the aqueduct. Sagittal and coronal sections of MRI and axial sections of X-ray CT proved to be useful in the diagnosis and classification of the holoprosencephaly, even without other invasive diagnostic procedures.

  3. X-ray tube current modulation and patient doses in chest CT.

    Science.gov (United States)

    He, Wenjun; Huda, Walter; Magill, Dennise; Tavrides, Emily; Yao, Hai

    2011-01-01

    The aim of the study was to investigate how patient effective doses vary as a function of X-ray tube projection angle, as well as the patient long axis, and quantify how X-ray tube current modulation affects patient doses in chest CT examinations. Chest examinations were simulated for a gantry CT scanner geometry with projections acquired for a beam width of 4 cm. PCXMC 2.0.1 was used to calculate patient effective doses at 15° intervals around the patient's isocentre, and at nine locations along the patient long axis. Idealised tube current modulation schemes were modelled as a function of the X-ray tube angle and the patient long axis. Tube current modulations were characterised by the modulation amplitude R, which was allowed to vary between 1.5 and 5. Effective dose maxima occur for anteroposterior projections at the location of the (radiosensitive) breasts. The maximum to minimum ratio of effective doses as a function of the patient long axis was 4.9, and as a function of the X-ray tube angle was 2.1. Doubling the value of R reduces effective doses from longitudinal modulation alone by ∼4% and from angular modulation alone by ∼2%. In chest CT, tube current modulation schemes currently have longitudinal R values of ∼2.2, and angular R values that range between 1.5 and 3.4. Current X-ray tube current modulation schemes are expected to reduce patient effective doses in chest CT examinations by ∼10%, with longitudinal modulation accounting for two-thirds and angular modulation for the remaining one-third.

  4. Lung ultrasound and chest x-ray for detecting pneumonia in an acute geriatric ward

    OpenAIRE

    2016-01-01

    Abstract Background: Our aim was to compare the accuracy of lung ultrasound (LUS) and standard chest x-ray (CXR) for diagnosing pneumonia in older patients with acute respiratory symptoms (dyspnea, cough, hemoptysis, and atypical chest pain) admitted to an acute-care geriatric ward. Methods: We enrolled 169 (80 M, 89 F) multimorbid patients aged 83.0 ± 9.2 years from January 1 to October 31, 2015. Each participant underwent CXR and bedside LUS within 6 hours from ward admission. LUS was perfo...

  5. Chest X ray changes in severe acute respiratory syndrome cases after discontinuation of glucocorticosteroids treatment

    Institute of Scientific and Technical Information of China (English)

    姚婉贞; 陈亚红; 张立强; 王筱宏; 孙永昌; 孙威; 韩江莉; 张福春; 郑亚安; 孙伯章; 贺蓓; 赵鸣武

    2004-01-01

    @@ Severe acute respiratory syndrome (SARS) is a disease identified in Asia, North America and Europe. The drugs for treatment and prevention of and vaccine for the disease are in research.1,2 There is still no agreement on glucocorticosteroid treatment of SARS. In treatment of SARS patients with glucocorticosteroids, we found 5 cases whose chest X ray changes were different from what the literature reported.

  6. Diagnosis of vertebral fractures on lateral chest X-ray: Intraobserver agreement of semi-quantitative vertebral fracture assessment

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    Jagt-Willems, H.C. van der, E-mail: Hvanderjagt@spaarneziekenhuis.nl [Department of Geriatrics, Slotervaart Hospital, Amsterdam (Netherlands); Department of Internal Medicine, Spaarne Hospital, Hoofddorp (Netherlands); Munster, B.C. van [Department of Internal Medicine, Academic Medical Center, Amsterdam (Netherlands); Department of Geriatrics, Gelre Hospitals, Apeldoorn (Netherlands); Leeflang, M. [Department of Geriatrics, Gelre Hospitals, Apeldoorn (Netherlands); Beuerle, E. [Department of Radiology, Slotervaart Hospital, Amsterdam (Netherlands); Tulner, C.R. [Department of Geriatrics, Slotervaart Hospital, Amsterdam (Netherlands); Lems, W.F. [Department of Rheumatology, VU Medical Center, Amsterdam (Netherlands)

    2014-12-15

    Highlights: • (Lateral) chest X-ray's are often performed in older individuals for various reasons. • Vertebral fractures are visualized on lateral chest X-ray, but the diagnosis of vertebral fractures is until now only validated on (lateral) spine X-ray's. • This study shows that a (lateral) chest X-ray is sufficient for the diagnosis of vertebral fractures. • Older individuals with a vertebral fracture on a (lateral) chest X-ray do not need further radiography with thoracic spine X-ray or vertebral fracture assessment with DXA. - Abstract: Background: In clinical practice lateral images of the chest are performed for various reasons. As these lateral chest X rays show the vertebrae of the thoracic and thoraco-lumbar region, we wondered if these X-rays can be used for evaluation of vertebral fractures instead of separate thoracic spine X-rays. Methods: To evaluate the agreement and intraobserver reliability of the semi-quantitative method for vertebral fractures on the lateral chest X-ray (X-chest) in comparison to the lateral thoracic spine X-ray (X-Tspine), two observers scored vertebral fractures on X-Tspine and twice on X-chest, separately, blinded and in different time periods. Agreement and Cohens’ kappa were calculated for a diagnosis of any fracture on patient level and on vertebral body level. The study was done in patients visiting an outpatient geriatric day clinic, with a high prevalence of vertebral fractures. Results: 109 patients were included. The intraobserver agreement for X-chest versus X-Tspine was 95–98% for the two levels of fracturing, with a Cohen's kappa of 0.88–0.91. The intraobserver agreement and reliability of the re-test on the X-chest showed an agreement between 91 and 98% with a Cohen's kappa of 0.81–0.93. More vertebrae were visible on the X-chest, mean 10.2, SD 0.66 versus mean 9.8, SD 0.73 on the X-Tspine (p < 0.001). Conclusion: The results show good agreement and intraobserver reliability on

  7. The chest X-ray image features of patients with severe SARS: a preliminary study

    Institute of Scientific and Technical Information of China (English)

    刘晋新; 唐小平; 江松峰; 陈碧华; 张烈光; 黄德扬; 黄务枝; 史红玲; 尹炽标; 陈金城

    2003-01-01

    Objective To study the chest X-ray image features of patients with severe SARS.Methods Chest X-ray image features in 36 patients with severe SARS were retrospectively analyzed. The image characteristics were compared with those of 224 patients with common SARS. Results The important chest X-ray imaging features of 36 patients with severe SARS included small patch of infiltration (n=27, 75.0%), large patch of infiltration (n=22, 61.1%), large area of lung consolidation (n=10, 27.3%), interstitial lung lesion (n=26, 72.2%), ground-glass shadow (n=28, 77.8%), irregular linear opacity (n=15, 41.7%), diffuse lung lesion (n=12, 33.3%), with single lung involved (n=9, 25.0%), and both lungs involved (n=32, 88.9%). The rates of large patch of infiltration, large area of lung consolidation, ground-glass shadow, diffuse lung lesion and involvement of both lungs in patients with severe SARS were significantly higher than those in patients with common type of SARS (all P<0.01). Out of the 11 severe SARS patients who died, nine had large area of ground-glass shadow with air bronchogram in both lungs before death.Conclusions Large patch of infiltration, large area of consolidation, ground-glass shadow, diffuse lung lesion and involvement of both lungs were the main X-ray image characteristics of patients with severe SARS. Large area of ground-glass shadow with air bronchogram in both lungs indicated a bad prognosis.

  8. STUDY OF TIME LAPSE IN FOREIGN BODY ASPIRATION IN RELATION TO CHEST X - RAY AND TYPE OF FOREIGN BODY

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    Salma

    2015-10-01

    Full Text Available INTRODUCTI ON: Foreign body aspiration in pediatrics is a potentially fatal accident which will continue until children explore their surroundings with their hand and mouth. Pediatric aspirations will persist until mankind exists. Not all foreign body aspirations are witnessed hence chances of delay in diagnosing an aspiration are high. Delay in diagnosis depends on site and character of foreign body aspirated. The chest x - ray findings and type of foreign body extracted vary depending on the duration the foreign body remains in airway . OBJECTIVE: To study the X - ray finding in pediatric airway aspiration and its relation to time lapse, the type and site of lodgment of foreign body extracted via bronchoscopy. The type of foreign body in relation to time lapse in aspiration. MATERIAL AND METHODS: This was a prospective study done in Bapuji child health institute and research center, JJM Medical College, Davangere . History and pre bronchoscopy x - Ray finding were noted for 65 children who were posted for suspicious bronchoscopy from August 2011 to September 2013. 11 children were excluded from study as they showed no foreign body on bronchoscopy. Time lapse in aspir ation and seeking medical care was noted. The bronchoscopic findings regarding site of foreign body lodgment and type of foreign body were recorded. The type of foreign body and variation of x - ray picture in relation to time lapse in aspiration were noted. Data collected was analyzed using descriptive statistics. RESULT: It was observed that mean age was 28 months. About 80% of the cases were between 1 to 3 years age. 82% (n=53/54 were radio lucent foreign body, only 1.5% (n=1/54 were radio o paque. Site of lodgment of foreign body was right main bronchus in 48% (n=26/54, left main bronchus 46% (n=25/54 , tracheal 1.85% (n=1/54, subglottic 1.85% (n=1/54, carinal 1.85% (n=1/54, multiple site i.e. left bronchus +right bronchus+ carinal 1.85% (n=1/54. Groundnut was most common

  9. Inter-observer agreement in interpreting chest X-rays on children with acute lower respiratory tract infections and concurrent wheezing

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    Carlos Bada

    Full Text Available CONTEXT AND OBJECTIVE: Many children with acute lower respiratory tract infections (ALRI present to the emergency ward with concurrent wheezing. A chest x-ray is often requested to rule out pneumonia. We assessed inter-observer agreement in interpreting x-rays on such children. DESIGNS AND SETTING: Prospective consecutive case study at Instituto de Salud del Niño, Lima, Peru. METHODS: Chest x-rays were obtained from eligible children younger than two years old with ALRI and concurrent wheezing who were seen in the emergency ward of a nationwide pediatric referral hospital. The x-rays were read independently by three different pediatric residents who were aware only that the children had a respiratory infection. All the children had received inhaled beta-adrenergic agonists before undergoing chest x-rays. Lobar and complicated pneumonia cases were excluded from the study. RESULTS: Two hundred x-rays were read. The overall kappa index was 0.2. The highest individual kappa values for specific x-ray findings ranged from 0.26 to 0.34 for rib horizontalization and from 0.14 to 0.31 for alveolar infiltrate. Inter-observer variation was intermediate for alveolar infiltrate (kappa 0.14 to 0.21 and for air bronchogram (kappa 0.13 to 0.23. Reinforcement of the bronchovascular network (kappa 0.10 to 0.16 and air trapping (kappa 0.05 to 0.20 had the lowest agreement. CONCLUSIONS: There was poor inter-observer agreement for chest x-ray interpretation on children with ALRI and concurrent wheezing seen at the emergency ward. This may preclude reliable diagnosing of pneumonia in settings where residents make management decisions regarding sick children. The effects of training on inter-observer variation need further studies.

  10. Prospective gated chest tomosynthesis using CNT X-ray source array

    Science.gov (United States)

    Shan, Jing; Burk, Laurel; Wu, Gongting; Lee, Yueh Z.; Heath, Michael D.; Wang, Xiaohui; Foos, David; Lu, Jianping; Zhou, Otto

    2015-03-01

    Chest tomosynthesis is a low-dose 3-D imaging modality that has been shown to have comparable sensitivity as CT in detecting lung nodules and other lung pathologies. We have recently demonstrated the feasibility of stationary chest tomosynthesis (s-DCT) using a distributed CNT X-ray source array. The technology allows acquisition of tomographic projections without moving the X-ray source. The electronically controlled CNT x-ray source also enables physiologically gated imaging, which will minimize image blur due to the patient's respiration motion. In this paper, we investigate the feasibility of prospective gated chest tomosynthesis using a bench-top s-DCT system with a CNT source array, a high- speed at panel detector and realistic patient respiratory signals captured using a pressure sensor. Tomosynthesis images of inflated pig lungs placed inside an anthropomorphic chest phantom were acquired at different respiration rate, with and without gating for image quality comparison. Metal beads of 2 mm diameter were placed on the pig lung for quantitative measure of the image quality. Without gating, the beads were blurred to 3:75 mm during a 3 s tomosynthesis acquisition. When gated to the end of the inhalation and exhalation phase the detected bead size reduced to 2:25 mm, much closer to the actual bead size. With gating the observed airway edges are sharper and there are more visible structural details in the lung. Our results demonstrated the feasibility of prospective gating in the s-DCT, which substantially reduces image blur associated with lung motion.

  11. The correlation between the chest X-ray classifications and the pathogens of hand–foot–mouth disease

    Directory of Open Access Journals (Sweden)

    Huan-guo Li

    2015-12-01

    Conclusions: There was some relativity between clinical grade and pathogens. The severe and critical HFMD were caused mainly by EV71, and the mild HFMD was caused mainly by other pathogens except EV71. There was no significant correlation between chest X-ray classification and pathogens, but in the same chest X-ray classification, the distribution of pathogens was not identical. For the limitations of this study, we will do more research in the future work.

  12. An image processing system for digital chest X-ray images.

    Science.gov (United States)

    Cocklin, M; Gourlay, A; Jackson, P; Kaye, G; Miessler, M; Kerr, I; Lams, P

    1984-01-01

    This paper investigates the requirements for image processing of digital chest X-ray images. These images are conventionally recorded on film and are characterised by large size, wide dynamic range and high resolution. X-ray detection systems are now becoming available for capturing these images directly in photoelectronic-digital form. In this report, the hardware and software facilities required for handling these images are described. These facilities include high resolution digital image displays, programmable video look up tables, image stores for image capture and processing and a full range of software tools for image manipulation. Examples are given of the application of digital image processing techniques to this class of image.

  13. Effective dose conversion coefficients for X-ray radiographs of the chest and the abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Lima, F.R.A. [Centro regional de Ciencias Nucleares, CRCN/CNEN, Rua Conego Barata, 999, Tamarineira, Recife, PE (Brazil); Kramer, R.; Vieira, J.W.; Khoury, H.J. [Departamento de Energia Nuclear, DEN/UFPE, Cidade Universitaria, Recife, PE (Brazil)]. E-mail: falima@cnen.gov.br

    2004-07-01

    The recently developed MAX (Male Adult voXel) and the FAXht (Female Adult voXel) head and trunk phantoms have been used to calculate organ and tissue equivalent dose conversion coefficients for X-ray radiographs of the chest and the abdomen as a function of source and field parameters, like voltage, filtration, field size, focus-to-skin distance, etc. Based on the equivalent doses to twenty three organs and tissues at risk, the effective dose has been determined and compared with corresponding data for others phantoms. The influence of different radiation transport codes, different tissue compositions and different human anatomies have been investigated separately. (Author)

  14. Chest radiographic findings of leptospirosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mee Hyun; Jung, Hee Tae; Lee, Young Joong; Yoon, Jong Sup [Hallym University College of Medicine, Seoul (Korea, Republic of)

    1986-04-15

    1. A study on chest radiographic findings of 54 cases with pneumonia like symptoms was performed. Of 54 cases, 8 cases were confirmed to be leptospirosis and 7 cases were leptospirosis combined with Korean hemorrhagic fever. 2. Of 8 cases of leptospirosis, 4 cases showed abnormal chest radiographic findings: acinar nodular type 2, massive confluent consolidation type 2. Of 7 cases of leptospirosis combined with Korean hemorrhagic fever: acinar nodular type 3, massive confluent consolidation type 1, and increased interstitial markings type 1 respectively. 3. It was considered to be difficult to diagnose the leptospirosis on chest radiographic findings alone, especially the case combined with Korean hemorrhagic fever.

  15. Atlas-based rib-bone detection in chest X-rays.

    Science.gov (United States)

    Candemir, Sema; Jaeger, Stefan; Antani, Sameer; Bagci, Ulas; Folio, Les R; Xu, Ziyue; Thoma, George

    2016-07-01

    This paper investigates using rib-bone atlases for automatic detection of rib-bones in chest X-rays (CXRs). We built a system that takes patient X-ray and model atlases as input and automatically computes the posterior rib borders with high accuracy and efficiency. In addition to conventional atlas, we propose two alternative atlases: (i) automatically computed rib bone models using Computed Tomography (CT) scans, and (ii) dual energy CXRs. We test the proposed approach with each model on 25 CXRs from the Japanese Society of Radiological Technology (JSRT) dataset and another 25 CXRs from the National Library of Medicine CXR dataset. We achieve an area under the ROC curve (AUC) of about 95% for Montgomery and 91% for JSRT datasets. Using the optimal operating point of the ROC curve, we achieve a segmentation accuracy of 88.91±1.8% for Montgomery and 85.48±3.3% for JSRT datasets. Our method produces comparable results with the state-of-the-art algorithms. The performance of our method is also excellent on challenging X-rays as it successfully addressed the rib-shape variance between patients and number of visible rib-bones due to patient respiration.

  16. A pilot study evaluating erect chest imaging in children, using the Lodox Statscan digital X-ray machine

    Directory of Open Access Journals (Sweden)

    Rupesh Baloo Daya

    2009-11-01

    Full Text Available ABSTRACT Background: Chest radiography accounts for a significant proportion of ionising radiation in children. The radiation dose of radiographs performed on the Lodox Statscan system has been shown to be lower than that of a computed radiography (CR system. The role of the Lodox Statscan (hereafter referred to as the Statscan in routine erect chest radiography in children has not been evaluated. Objective: To evaluate the image quality and diagnostic accuracy of erect paediatric chest radiographs obtained with the Statscan and compare this with conventional erect chest images obtained with a CR system. Materials and Methods: Thirty three children with suspected chest pathology were enrolled randomly over a period of three months. Erect chest radiographs were obtained with the Statscan, and a Shimadzu R-20J X-ray machine coupled with a Fuji FCR 5000 CR system. Image quality and diagnostic accuracy and diagnostic capability were evaluated between the two modalities. Results: The erect Statscan allowed superior visualisation of the three major airways. Statscan images however, demonstrated exposure and movement artifacts with hemidiaphragms and ribs most prone to movement. Bronchovascular clarity was also considered unsatisfactory on the Statscan images. Conclusion: The Statscan has limitations in erect chest radiography in terms of movement artefacts, exposure fluctuations, and poor definition of lung markings. Despite this, the Statscan allows better visualisation of the major airways, equivalent to a ‘high KV’ film at a fraction of the radiation dose. This supports the finding of an earlier study evaluating Statscan images in trauma cases, where the images were taken supine. Statscan has great potential in assisting in the diagnosis of childhood tuberculosis where airway narrowing occurs as a result of nodal compression.

  17. The Characteristics and Dynamic Changes of X-Ray Chest Film in 50 Patients with Severe Acute Respiratory Syndrome

    Institute of Scientific and Technical Information of China (English)

    马俊义; 李智岗; 赵增毅; 孙武装; 王颖

    2003-01-01

    @@ Severe acute respiratory syndrome (SARS) is a new acute infectious disease which quickly spreads and develops, resulting in high mortality. Since there lacks any diagnostic method with high specificity and sensitivity, the X-ray chest film becomes an important measure for diagnosis for SARS. Therefore, to understand the characteristics of X-ray chest film in SARS patients and get to know the rule of its dynamic changes is meaningful for SARS diagnosing, treating and prognosing. The characteristics and dynamic changes of chest film in 50 SARS patients in Hebei Province were analysed by the authors and reported as follows.

  18. A Solitary Feature-based Lung Nodule Detection Approach for Chest X-Ray Radiographs.

    Science.gov (United States)

    Li, Xuechen; Shen, Linlin; Luo, Suhuai

    2017-01-31

    Lung cancer is one of the most deadly diseases. It has a high death rate and its incidence rate has been increasing all over the world. Lung cancer appears as a solitary nodule in chest x-ray radiograph (CXR). Therefore, lung nodule detection in CXR could have a significant impact on early detection of lung cancer. Radiologists define a lung nodule in chest x-ray radiographs as "solitary white nodule-like blob". However, the solitary feature has not been employed for lung nodule detection before. In this paper, a solitary feature-based lung nodule detection method was proposed. We employed stationary wavelet transform and convergence index filter to extract the texture features and used AdaBoost to generate white nodule-likeness map. A solitary feature was defined to evaluate the isolation degree of candidates. Both the isolation degree and the white nodule-likeness were used as final evaluation of lung nodule candidates. The proposed method shows better performance and robustness than those reported in previous research. More than 80% and 93% of lung nodules in the lung field in the JSRT database were detected when the false positives per image was two and five, respectively. The proposed approach has the potential of being used in clinical practice.

  19. Visualizing and enhancing a deep learning framework using patients age and gender for chest x-ray image retrieval

    Science.gov (United States)

    Anavi, Yaron; Kogan, Ilya; Gelbart, Elad; Geva, Ofer; Greenspan, Hayit

    2016-03-01

    We explore the combination of text metadata, such as patients' age and gender, with image-based features, for X-ray chest pathology image retrieval. We focus on a feature set extracted from a pre-trained deep convolutional network shown in earlier work to achieve state-of-the-art results. Two distance measures are explored: a descriptor-based measure, which computes the distance between image descriptors, and a classification-based measure, which performed by a comparison of the corresponding SVM classification probabilities. We show that retrieval results increase once the age and gender information combined with the features extracted from the last layers of the network, with best results using the classification-based scheme. Visualization of the X-ray data is presented by embedding the high dimensional deep learning features in a 2-D dimensional space while preserving the pairwise distances using the t-SNE algorithm. The 2-D visualization gives the unique ability to find groups of X-ray images that are similar to the query image and among themselves, which is a characteristic we do not see in a 1-D traditional ranking.

  20. letter to editor: Swine Flu: Concern for Infection Control in the Procedure of Patient Preparation for Chest X-Ray

    Directory of Open Access Journals (Sweden)

    V. Wiwanitkit

    2009-11-01

    Full Text Available Dear editor:"n"nSwine flu is a new emerging atypical H1N1 influenza virus infection. Nowadays swine flu pandemic has become a global public health threat.1 As there are several epidemic foci of swine flu around the world and there are many infected cases, it is necessary for every country to prepare for management. Chest x-ray is an important investigation for the confirmed infected cases as well as highly suspicious cases. There must be specific concern for infection control in the procedure of patient preparation for chest x-ray. In routine clinical practice, separation of the patients and using specific isolated parts are suggested for general clinic; however, this might not be possible for the x-ray unit. It is routinely not possible to separate the x-ray room specifically for this group of patients. There must be a special communication system between the ward and the x-ray unit for early preparation. The process must be managed as a fast track procedure and preparation of a special room based on disinfectant principles before and after each x-ray procedure. In addition, preparation of the patients according to basic infection control process such as wearing masks and hand washing before the x-ray procedure are other precautionary measurements.    

  1. Radiation doses to paediatric patients and comforters undergoing chest X rays.

    Science.gov (United States)

    Sulieman, A; Vlychou, M; Tsougos, I; Theodorou, K

    2011-09-01

    Pneumonia is an important cause of hospital admission among children in the developed world and it is estimated to be responsible for 3-18 % of all paediatric admissions. Chest X ray is an important examination for pneumonia diagnosis and for evaluation of complications. This study aims to determine the entrance surface dose (ESD), organ, effective doses and propose a local diagnostic reference level. The study was carried out at the university hospital of Larissa, Greece. Patients were divided into three groups: organ and effective doses were estimated using National Radiological Protection Board software. The ESD was determined by thermoluminescent dosemeters for 132 children and 76 comforters. The average ESD value was 55 ± 8 µGy. The effective dose for patients was 11.2 ± 5 µSv. The mean radiation dose for comforter is 22 ± 3 µGy. The radiation dose to the patients is well within dose constraint, in the light of the current practice.

  2. A study to compare chest X-ray reports on overseas nursing recruits.

    LENUS (Irish Health Repository)

    Power, S

    2010-05-01

    This study was carried out to assess if there was a difference in the Chest X- ray (CXR) report on recruited nurses carried out overseas and later repeated in Ireland. This study was carried out in two Irish teaching hospitals. The subjects of this study comprised all overseas nurses recruited in each of the two hospitals within the defined period. The total number of subjects recruited from the 2 two centres was 84. Only nurses that had a repeat CXR were included in this study. 6\\/84 (7%) of the CXR that were initially reported as normal were subsequently reported as abnormal and were later diagnosed as Latent TB. 2\\/84(2%) of the CXR that were reported as abnormal were subsequently reported as normal. The data collected in this study has demonstrated that there was a significant difference in the CXR report from overseas and the CXR report in Ireland.

  3. The completeness of chest X-ray procedure codes in the Danish National Patient Registry

    Directory of Open Access Journals (Sweden)

    Hjertholm P

    2017-03-01

    Full Text Available Peter Hjertholm,1 Kaare Rud Flarup,1 Louise Mahncke Guldbrandt,1 Peter Vedsted1,2 1Research Center for Cancer Diagnosis in Primary Care, Department of Public Health, 2University Clinic for Innovative Health Care Delivery, Diagnostic Centre, Silkeborg Hospital, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark Objective: The aim of this validation study was to assess the completeness of the registrations of chest X-rays (CXR in two different versions of the Danish National Patient Registry (DNPR. Material and methods: We included electronic record data on CXR performed on patients aged 40 to 99 years from nine radiology departments covering 20 Danish hospitals. From each department, we included data from three randomly selected weeks between 2004 and 2011 (reference standard. In two versions of the DNPR from the State Serum Institute (SSI and Statistics Denmark, respectively, we investigated the proportion of registered CXR compared to the reference standard. Furthermore, we compared the completeness of the recorded data according to the responsible department (main department. Results: We identified 11,235 patients and 12,513 CXR in the reference standard. The data from the SSI contained 12,265 (98% CXR, whereas the data from Statistics Denmark comprised 9,151 (73.1% CXR. The completeness of the SSI data was fairly constant across years, radiology departments, medical specialties, and age groups. The data from Statistics Denmark was almost complete in 2011 (95.8%. However, for the remaining study period, the data with radiology departments registered as the main department were lacking in the version from Statistics Denmark, and so the overall completeness was 73.1%. Conclusion: The completeness of CXR registrations varied between 98% and 73% depending on the information source, and this should be considered when investigating radiology services in the basis of DNPR. Keywords: chest X-ray, Danish National Patient Registry

  4. Significance of findings of both emergency chest X-ray and thoracic computed tomography routinely performed at the emergency unit in 102 polytrauma patients. A prospective study; Relevanz der Befunde von Thoraxroentgen und Thorax-CT im routinemaessigen Schockraumeinsatz bei 102 polytraumatisierten Patienten. Eine prospektive Studie

    Energy Technology Data Exchange (ETDEWEB)

    Grieser, T.; Buehne, K.H.; Haeuser, H.; Bohndorf, K. [Zentralklinikum Augsburg (Germany). Klinik fuer Diagnostische Radiologie und Neuroradiologie

    2001-01-01

    Purpose: To evaluate prospectively whether and to what extent both thoracic computed tomography (Tx-CT) and supine X-ray of the chest (Rx-Tx) are able to show additional findings that are therapeutically relevant. Patients and Methods: According to a fixed study protocol, we performed Rx-Tx and Tx-CT in 102 consecutive, haemodynamically stable polytrauma patients (mean age, 41.2 yrs; age range, 12-93 yrs). Findings of therapeutical relevance drawn from both Tx-CT and Rx-Tx, and urgent interventions indicated by an attending trauma team were documented on a standardized evaluation sheet immediately. Any change in the patient's management that is different from routine life-saving procedures, and any therapeutical intervention done in the emergency room or elsewhere (operating theatre, angiographic facility) were considered therapeutically relevant. Results: Of 102 patients, 43 (42.2%) had a total of 51 therapeutically relevant findings. Rx-Tx alone yielded 23 relevant findings (45.1%) in 23 patients (22.5%). Of them, Tx-CT has shown additional important findings in 7 patients (30.4%). When Tx-CT alone is considered, it revealed 22 new findings of therapeutical relevance (43.2%) in 20 patients (46.5%). Altogether, Tx-CT was able to show 30 relevant findings in 27 patients, i.e., there was a therapeutical benefit for 26.5% of all polytrauma patients included. Most frequently, there was a need for chest-tube insertion (n=29). Conclusions: Polytrauma patients if haemodynamically stable may profit from computed tomography of the chest when therapeutically relevant thoracic injuries are looked for or early therapeutical interventions are to be checked. However, chest X-ray should stay as a 'front-line' screening method because of its superbly quick feasibility and availability. (orig.) [German] Ziel: Die prospektive Studie soll klaeren, ob und inwieweit eine Thoraxcomputertomographie (Tx-CT) unter Schockraumbedingungen gegenueber der Roentgen

  5. Aspergillus and mucormycosis presenting with normal chest X-ray in an immunocompromised host.

    Science.gov (United States)

    Gupta, Vipin; Rajagopalan, Natarajan; Patil, Mahantesh; Shivaprasad, C

    2014-04-09

    Invasive aspergillus and mucormycosis infection are not uncommon in immunocompromised individuals. Endobronchial fungal infections have been reported in the literature, especially in patient's with diabetes complicated by diabetic ketoacidosis, but end bronchial coinfection with aspergillus and mucormycosis without pulmonary involvement has not been described in the literature. We report the case of a woman with diabetes who presented with gastrointestinal symptoms, ketoacidosis and respiratory distress, with an apparently normal chest X-ray. Investigations revealed a cavitatory lesion in the left lower lobe of the lungs on CT scan. Bronchoscopy revealed intense mucosal oedema and whitish plaques at the lower end of the trachea and right main stem bronchus with a normal left bronchial tree. Microbiological and pathological results confirmed aspergillus and mucormycosis. Despite aggressive medical management, the patient deteriorated and died of respiratory failure. Strong suspicion of invasive fungal infections in immunocompromised patients with respiratory failure and minimal chest infiltrates, early fibreoptic bronchoscopy and early aggressive treatment is crucial for the patient's survival.

  6. Relevance of an incidental chest finding

    Science.gov (United States)

    Cortés-Télles, Arturo; Mendoza, Daniel

    2012-01-01

    Solitary pulmonary nodule represents 0.2% of incidental findings in routine chest X-ray images. One of the main diagnoses includes lung cancer in which small-cell subtype has a poor survival rate. Recently, a new classification has been proposed including the very limited disease stage (VLD stage) or T1-T2N0M0 with better survival rate, specifically in those patients who are treated with surgery. However, current recommendations postulate that surgery remains controversial as a first-line treatment in this stage. We present the case of a 46-year-old female referred to our hospital with a preoperative diagnosis of a solitary pulmonary nodule. On initial approach, a biopsy revealed a small cell lung cancer. She received multimodal therapy with surgery, chemotherapy, and prophylactic cranial irradiation and is currently alive without recurrence on a 2-year follow-up. PMID:22345914

  7. Routinely obtained chest X-rays after elective video-assisted thoracoscopic surgery can be omitted in most patients; a retrospective, observational study

    DEFF Research Database (Denmark)

    Bjerregaard, Lars S; Jensen, Katrine; Petersen, René Horsleben;

    2015-01-01

    divided into three groups according to the degree of pulmonary resection. The chest X-rays (obtained anterior-posterior in one plane with the patient in the supine position) were categorized as abnormal if showing pneumothorax >5 cm, possible intra-thoracic bleeding and/or a displaced chest tube. Medical....... Proportions of abnormal chest X-rays were unequally distributed between groups (p pneumothorax >5 cm and one showed a kinked chest...

  8. Chest X-ray Findings of Woodworkers, Epidemiological and Experimental Study

    OpenAIRE

    Okita, Isao; Nakanishi, Takashi; Asaeda, Genkichi

    1983-01-01

    Mass examination of the ladorers in wood and products industries was conducted. The workers showing abnormal chest x-ray findings were over 40years of age and had worked longer than 20 years in these industries. The abnormal x-ray findings were linear and small opacities. From these observation, it is likely that the abnormal findings of chest x-ray films were associated with wooden dust. The experimental studies by infusing paulowina dust into the lungs of rats showed the foreign body granul...

  9. Cystic Fibrosis Chest X-Ray Findings: A Teaching Analog

    Science.gov (United States)

    2008-07-01

    methicilin-resistant S. aureus. In newborns , the TORCHES infections predominate: Toxoplasmosis, Rubella, CMV, Herpes, Syphilis, and others. The first...of alveolar filling resulting in increased density on radiographs. The five common “sources” of a consolidation are hemorrhage , exudates...exposure. Table 3: Differential Diagnosis for Air Bronchograms Consolidation Hemorrhage (Blood) Embolism Trauma, contusion Exudate (Pus

  10. The completeness of chest X-ray procedure codes in the Danish National Patient Registry

    Science.gov (United States)

    Hjertholm, Peter; Flarup, Kaare Rud; Guldbrandt, Louise Mahncke; Vedsted, Peter

    2017-01-01

    Objective The aim of this validation study was to assess the completeness of the registrations of chest X-rays (CXR) in two different versions of the Danish National Patient Registry (DNPR). Material and methods We included electronic record data on CXR performed on patients aged 40 to 99 years from nine radiology departments covering 20 Danish hospitals. From each department, we included data from three randomly selected weeks between 2004 and 2011 (reference standard). In two versions of the DNPR from the State Serum Institute (SSI) and Statistics Denmark, respectively, we investigated the proportion of registered CXR compared to the reference standard. Furthermore, we compared the completeness of the recorded data according to the responsible department (main department). Results We identified 11,235 patients and 12,513 CXR in the reference standard. The data from the SSI contained 12,265 (98%) CXR, whereas the data from Statistics Denmark comprised 9,151 (73.1%) CXR. The completeness of the SSI data was fairly constant across years, radiology departments, medical specialties, and age groups. The data from Statistics Denmark was almost complete in 2011 (95.8%). However, for the remaining study period, the data with radiology departments registered as the main department were lacking in the version from Statistics Denmark, and so the overall completeness was 73.1%. Conclusion The completeness of CXR registrations varied between 98% and 73% depending on the information source, and this should be considered when investigating radiology services in the basis of DNPR. PMID:28293121

  11. 重症甲型H1N1流感患者的胸部X线和CT特征分析%Chest X-ray Radiographic and CT Findings in Severe A(H1N1) Virus Infection

    Institute of Scientific and Technical Information of China (English)

    陈伟; 何波; 袁峰; 孙学进; 赵卫

    2011-01-01

    Objective To study X-ray radiographic and CT findings in patients with severe A (H1N1)virus infection. Method We reviewed the chest X-ray radiographic and CT findings of 24 patients with confrmed severe A (H1N1) virus infection in our hospital from November 2009 to December 2009. Results (1) The initial radiograph was normal in 4 patients among 24 patients with severe A (H1N1) virus infection. (2) Chest radiography and CT found ground-glass opacity in the lungs accounted for 53% and 67%, and mixed groundglass opacity with consolidation accounted for 37% and 62%. Ground-glass is mainly located in the lower part of the pleura around the lung, and ground-glass with consolidation is mainly located in the lower lung and central lung. (3) Chest radiography and CT found 3 cases and 5 cases of pleural effusion, and 2 cases and 9 cases of pleural thickening, respectively. (4) No patients were found with evident hilar or mediastinal lymph node enlargement by radiography or CT scans. Conclusions The predominant radiographic and CT findings are ground-glass opacity, following by ground- glass opacity with consolidation, without mediastinal and hilar lymph node enlargement, and the pleura can be involved on both chest radiography and CT. The findings of chest radiography and CT are consistent, but CT can find the lung lesions earlier than chest radiograph. CT can show the morphology and distribution of the lesions more clearly, so can increase the positive rate of lung lesions in severe A (H1N1). Also the chest radiography and CT can provide more clinical information to help clinicians find lesions in the lung early, give treatment in time, observe disease development and clinical evaluation.%目的 探讨重症甲型H1N1流感患者的胸部X线及CT表现.方法 回顾性分析经确诊的24例重症甲型H1N1流感患者的胸部X线及CT表现.结果 (1)24例中4例患者入院时胸部X线检察无异常发现;(2)X线及CT发现肺部磨玻璃影分别占53%、67

  12. FINDING FOSSIL GROUPS: OPTICAL IDENTIFICATION AND X-RAY CONFIRMATION

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Eric D. [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 (United States); Rykoff, Eli S. [E.O. Lawrence Berkeley National Lab, 1 Cyclotron Rd., Berkeley, CA 94720 (United States); Dupke, Renato A. [Department of Astronomy, University of Michigan, 500 Church St., Ann Arbor, MI 48109 (United States); Mendes de Oliveira, Claudia; Proctor, Robert N. [Departamento de Astronomia, Instituto de Astronomia, Geofisica e Ciencias Atmosfericas da Universidade de Sao Paulo, Rua do Matao 1226, Cidade Universitaria, 05508-090 Sao Paulo (Brazil); Lopes de Oliveira, Raimundo [Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, Caixa Postal 369, 13560-970 Sao Carlos, SP (Brazil); Garmire, Gordon P. [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Koester, Benjamin P. [Department of Astronomy and Astrophysics, The University of Chicago, Chicago, IL 60637 (United States); McKay, Timothy A., E-mail: milleric@mit.edu [Department of Physics, University of Michigan, 450 Church St., Ann Arbor, MI 48109 (United States)

    2012-03-10

    We report the discovery of 12 new fossil groups (FGs) of galaxies, systems dominated by a single giant elliptical galaxy and cluster-scale gravitational potential, but lacking the population of bright galaxies typically seen in galaxy clusters. These FGs, selected from the maxBCG optical cluster catalog, were detected in snapshot observations with the Chandra X-ray Observatory. We detail the highly successful selection method, with an 80% success rate in identifying 12 FGs from our target sample of 15 candidates. For 11 of the systems, we determine the X-ray luminosity, temperature, and hydrostatic mass, which do not deviate significantly from expectations for normal systems, spanning a range typical of rich groups and poor clusters of galaxies. A small number of detected FGs are morphologically irregular, possibly due to past mergers, interaction of the intra-group medium with a central active galactic nucleus (AGN), or superposition of multiple massive halos. Two-thirds of the X-ray-detected FGs exhibit X-ray emission associated with the central brightest cluster galaxy (BCG), although we are unable to distinguish between AGN and extended thermal galaxy emission using the current data. This sample representing a large increase in the number of known FGs, will be invaluable for future planned observations to determine FG temperature, gas density, metal abundance, and mass distributions, and to compare to normal (non-fossil) systems. Finally, the presence of a population of galaxy-poor systems may bias mass function determinations that measure richness from galaxy counts. When used to constrain power spectrum normalization and {Omega}{sub m}, these biased mass functions may in turn bias these results.

  13. [The chest CT findings and pathologic findings of pulmonary tuberculosis].

    Science.gov (United States)

    Ogata, Hideo

    2009-08-01

    The past research of the radiologic manifestations of pulmonary tuberculosis in Japan was based on morphological pathology of the untreated patient autopsy. I would like to show the chest CT scan of tuberculosis diseases with caseous granuloma at its exudative reaction, proliferative reaction, productive reaction, cirrhotic reaction until self cure. This progress reflects the normal cell mediated immunological responses. Also I would like to show the cavitation of granuloma, which results from liquefaction of caseous materials during the course and results in the formation of the source of infection. And finally I would like to show the morphological differences of acinous lesion, acino-nodular lesion and caseous lobular pneumonia. These differences reflect the amount of bacilli disseminated in the peripheral parts under the lobules. In this study, I do not show old age cases and HIV positive cases, who do not form typical granuloma due to the decreased cell mediated immnunity and whose X ray findings are atypical.

  14. Finding Supernova Ia Progenitors with the Chandra X-ray Observatory

    DEFF Research Database (Denmark)

    Nielsen, Mikkel T. B.; Nelemans, Gijs; Voss, Rasmus

    2011-01-01

    We examine pre-supernova Chandra images to find X-ray luminosities of type Ia supernova progenitors. At present, we have one possible direct detection and upper limits for the X-ray luminosities of a number of other supernova progenitors. The method has also yielded a possible detection of a X...

  15. European Guidelines for AP/PA chest X-rays: routinely satisfiable in a paediatric radiology division?

    Energy Technology Data Exchange (ETDEWEB)

    Tschauner, Sebastian; Marterer, Robert; Guebitz, Michael; Weissensteiner, Sabine; Sorantin, Erich [Medical University of Graz, Division of Paediatric Radiology, Department of Radiology, Graz (Austria); Kalmar, Peter I. [Medical University of Graz, Division of Vascular and Interventional Radiology, Department of Radiology, Graz (Austria); Talakic, Emina [Medical University of Graz, Division of General Radiological Diagnostics, Department of Radiology, Graz (Austria)

    2016-02-15

    Accurate collimation helps to reduce unnecessary irradiation and improves radiographic image quality, which is especially important in the radiosensitive paediatric population. For AP/PA chest radiographs in children, a minimal field size (MinFS) from ''just above the lung apices'' to ''T12/L1'' with age-dependent tolerance is suggested by the 1996 European Commission (EC) guidelines, which were examined qualitatively and quantitatively at a paediatric radiology division. Five hundred ninety-eight unprocessed chest X-rays (45 % boys, 55 % girls; mean age 3.9 years, range 0-18 years) were analysed with a self-developed tool. Qualitative standards were assessed based on the EC guidelines, as well as the overexposed field size and needlessly irradiated tissue compared to the MinFS. While qualitative guideline recommendations were satisfied, mean overexposure of +45.1 ± 18.9 % (range +10.2 % to +107.9 %) and tissue overexposure of +33.3 ± 13.3 % were found. Only 4 % (26/598) of the examined X-rays completely fulfilled the EC guidelines. This study presents a new chest radiography quality control tool which allows assessment of field sizes, distances, overexposures and quality parameters based on the EC guidelines. Utilising this tool, we detected inadequate field sizes, inspiration depths, and patient positioning. Furthermore, some debatable EC guideline aspects were revealed. (orig.)

  16. Anatomy-based transmission factors for technique optimization in portable chest x-ray

    Science.gov (United States)

    Liptak, Christopher L.; Tovey, Deborah; Segars, William P.; Dong, Frank D.; Li, Xiang

    2015-03-01

    Portable x-ray examinations often account for a large percentage of all radiographic examinations. Currently, portable examinations do not employ automatic exposure control (AEC). To aid in the design of a size-specific technique chart, acrylic slabs of various thicknesses are often used to estimate x-ray transmission for patients of various body thicknesses. This approach, while simple, does not account for patient anatomy, tissue heterogeneity, and the attenuation properties of the human body. To better account for these factors, in this work, we determined x-ray transmission factors using computational patient models that are anatomically realistic. A Monte Carlo program was developed to model a portable x-ray system. Detailed modeling was done of the x-ray spectrum, detector positioning, collimation, and source-to-detector distance. Simulations were performed using 18 computational patient models from the extended cardiac-torso (XCAT) family (9 males, 9 females; age range: 2-58 years; weight range: 12-117 kg). The ratio of air kerma at the detector with and without a patient model was calculated as the transmission factor. Our study showed that the transmission factor decreased exponentially with increasing patient thickness. For the range of patient thicknesses examined (12-28 cm), the transmission factor ranged from approximately 21% to 1.9% when the air kerma used in the calculation represented an average over the entire imaging field of view. The transmission factor ranged from approximately 21% to 3.6% when the air kerma used in the calculation represented the average signals from two discrete AEC cells behind the lung fields. These exponential relationships may be used to optimize imaging techniques for patients of various body thicknesses to aid in the design of clinical technique charts.

  17. Entrance surface dose and image quality: comparison of adult chest and abdominal X-ray examinations in general practitioner clinics, public and private hospitals in Malaysia.

    Science.gov (United States)

    Hambali, Ahmad Shariff; Ng, Kwan-Hoong; Abdullah, Basri Johan Jeet; Wang, Hwee-Beng; Jamal, Noriah; Spelic, David C; Suleiman, Orhan H

    2009-01-01

    This study was undertaken to compare the entrance surface dose (ESD) and image quality of adult chest and abdominal X-ray examinations conducted at general practitioner (GP) clinics, and public and private hospitals in Malaysia. The surveyed facilities were randomly selected within a given category (28 GP clinics, 20 public hospitals and 15 private hospitals). Only departmental X-ray units were involved in the survey. Chest examinations were done at all facilities, while only hospitals performed abdominal examinations. This study used the x-ray attenuation phantoms and protocols developed for the Nationwide Evaluation of X-ray Trends (NEXT) survey program in the United States. The ESD was calculated from measurements of exposure and clinical geometry. An image quality test tool was used to evaluate the low-contrast detectability and high-contrast detail performance under typical clinical conditions. The median ESD value for the adult chest X-ray examination was the highest (0.25 mGy) at GP clinics, followed by private hospitals (0.22 mGy) and public hospitals (0.17 mGy). The median ESD for the adult abdominal X-ray examination at public hospitals (3.35 mGy) was higher than that for private hospitals (2.81 mGy). Results of image quality assessment for the chest X-ray examination show that all facility types have a similar median spatial resolution and low-contrast detectability. For the abdominal X-ray examination, public hospitals have a similar median spatial resolution but larger low-contrast detectability compared with private hospitals. The results of this survey clearly show that there is room for further improvement in performing chest and abdominal X-ray examinations in Malaysia.

  18. Which method is best for an early accurate diagnosis of acute heart failure? Comparison between lung ultrasound, chest X-ray and NT pro-BNP performance: a prospective study.

    Science.gov (United States)

    Sartini, Stefano; Frizzi, Jacopo; Borselli, Matteo; Sarcoli, Elisabetta; Granai, Carolina; Gialli, Veronica; Cevenini, Gabriele; Guazzi, Gianni; Bruni, Fulvio; Gonnelli, Stefano; Pastorelli, Marcello

    2016-07-11

    Acute heart failure is a common condition among adults presenting with dyspnea in the Emergency Department (ED), still the diagnosis is challenging as objective standardized criteria are lacking. First line work-up, other then clinical findings, is nowadays made with lung ultrasound imaging study, chest X-ray study and brain natriuretic peptide (BNP) level determination; however, it is not clear which is the best diagnostic test to be used and whether there is any real benefit for clinical judgement. We set up this study to compare the performances of these three diagnostic tools; furthermore, we combined them to find the best possible approach to dyspneic patients. This is a prospective observational study based in the ED. We enrolled adults presenting with dyspnea not trauma-related, they underwent lung ultrasound, and chest X-ray studies, and NT pro-BNP level determination. Then we compared the results with the diagnosis of acute heart failure established by an independent panel of experts. 236 patients were enrolled in the study. We find sensitivity and specificity for lung ultrasound of 57.73 and 87.97 %, for chest X-ray 74.49 and 86.26 %, for NT pro-BNP 97.59 and 27.56 %, respectively. Combining together the chest X-ray and lung ultrasound, we find the best overall performance with 84.69 % sensitivity, 77.69 % specificity and 87.07 % negative predictive value. From our results, we could not identify the "best test" to diagnose acute heart failure in an emergency setting, although we could suggest that a stepwise workup combining chest X-ray and lung ultrasound at first, then for those negative, a determination of NT pro-BNP assay would be a reasonable approach to the dyspneic patient.

  19. Chandra Resolves Cosmic X-ray Glow and Finds Mysterious New Sources

    Science.gov (United States)

    2000-01-01

    While taking a giant leap towards solving one of the greatest mysteries of X-ray astronomy, NASA's Chandra X-ray Observatory also may have revealed the most distant objects ever seen in the universe and discovered two puzzling new types of cosmic objects. Not bad for being on the job only five months. Chandra has resolved most of the X-ray background, a pervasive glow of X-rays throughout the universe, first discovered in the early days of space exploration. Before now, scientists have not been able to discern the background's origin, because no X-ray telescope until Chandra has had both the angular resolution and sensitivity to resolve it. "This is a major discovery," said Dr. Alan Bunner, Director of NASA's Structure andEvolution of the universe science theme. "Since it was first observed thirty-seven years ago, understanding the source of the X-ray background has been aHoly Grail of X-ray astronomy. Now, it is within reach." The results of the observation will be discussed today at the 195th national meeting of the American Astronomical Society in Atlanta, Georgia. An article describing this work has been submitted to the journal Nature by Dr. Richard Mushotzky, of NASA Goddard Space Flight Center, Greenbelt, Md., Drs. Lennox Cowie and Amy Barger at the University of Hawaii, Honolulu, and Dr. Keith Arnaud of the University of Maryland, College Park. "We are all very excited by this finding," said Mushotzky. "The resolution of most of the hard X-ray background during the first few months of the Chandra mission is a tribute to the power of this observatory and bodes extremely well for its scientific future," Scientists have known about the X-ray glow, called the X-ray background, since the dawn of X-ray astronomy in the early 1960s. They have been unable to discern its origin, however, for no X-ray telescope until Chandra has had both the angular resolution and sensitivity to resolve it. The German-led ROSAT mission, now completed, resolved much of the lower

  20. Chest X-rays and associated clinical parameters in pulmonary Tubercolosis cases from the National Tubercolosis Program, Mumbai, India

    Directory of Open Access Journals (Sweden)

    Yatin N. Dholakia

    2012-01-01

    Full Text Available The study was carried out in pulmonary tuberculosis (PTB patients from the local Tuberculosis control programme, Mumbai, India. It examined features of chest X-rays and their correlation with clinical parameters for possible application in suspected multidrug resistant TB (MDRTB and to predict outcome in new and treatment failure PTB cases. X-ray features (infiltrate, cavitation, miliary shadows, pleural effusion, mediastinal lymphadenopathy and extent of lesions were analyzed to identify associations with biological/clinical parameters through univariate and multivariate logistic regression. Failures demonstrated associations between extensive lesions and high glycosylated hemoglobin (GHb levels (P=0.028 and male gender (P=0.03. An association was also detected between cavitation and MDR (P=0.048. In new cases, bilateral cavities were associated with MDR (P=0.018 and male gender (P=0.01, low body mass index with infiltrates (P=0.008, and smoking with cavitation (P=0.0238. Strains belonging to the Manu1 spoligotype were associated with mild lesions (P=0.002. Poor outcome showed borderline significance with extensive lesions at onset (P=0.053. Furthermore, amongst new cases, smoking, the Central Asian Strain (CAS spoligotype and high GHb were associated with cavitation, whereas only CAS spoligotypes and high GHb were associated with extensive lesions. The study highlighted associations between certain clinical parameters and X-ray evidence which support the potential of X-rays to predict TB, MDRTB and poor outcome. The use of Xrays as an additional tool to shorten diagnostic delay and shortlist MDR suspects amongst nonresponders to TB treatment should be explored in a setting with limited resources coping with a high MDR case load such as Mumbai.

  1. Diagnostic Utility of Chest X-rays in Neonatal Respiratory Distress: Determining the Sensitivity and Specificity

    Directory of Open Access Journals (Sweden)

    Hassan Mottaghi Moghadam shahri

    2014-11-01

    Full Text Available Background: Chest radiography is one of the most usual diagnostic tools for respiratory distress. Objective: The purpose of this study is to assess the specificity, sensitivity and clinical value of chest radiography of neonates with respiratory distress.Patients and Methods: A descriptive- analytical study was conducted on 102 neonates that were in neonatal intensive care unit of Imam Reza and 22 Bahman Hospitals because of respiratory distress. After confirming the neonate's respiratory distress and taking chest radiography, the radiography was described by a radiologist and final diagnosis was confirmed. Results: Most of the neonates (64.7% were born with caesarian section and were premature (78.4%. Respiratory distress syndrome (RDS was the most common reason for respiratory distress (38.2%. Chest radiography had the most sensitivity and specificity in pneumothorax and hernia (100%. For pneumosepsis, radiography had 73% sensitivity and 87% specificity, for RDS the sensitivity and specificity were 35% and 82% respectively, for congenital heart disease sensitivity of zero and specificity of 98% and for Transient tachypnea of neonates (TTN sensitivity of zero and specificity of 100%. The conformity of clinical and radiography was also calculated as 79.4% in respiratory distress Discussion and Conclusion: Although chest radiography is used as one of the most usual and accessible diagnostic tools in respiratory distress syndrome, but inaccurate specificity and sensitivity in some disease must be considered, especially in neonates.

  2. Clinical importance of digitized chest X-ray for detection of pulmonary infiltrations in bone marrow transplant patients during aplasia; Wertigkeit der digitalen Thoraxaufnahme bei der Detektion von Lungeninfiltraten knochenmarktransplantierten Patienten in der Aplasie

    Energy Technology Data Exchange (ETDEWEB)

    Weber, C.; Maas, R.; Steiner, P.; Kramer, J.; Bumann, D.; Buecheler, E. [Universitaetskrankenhaus Eppendorf, Hamburg (Germany). Abt. fuer Roentgendiagnostik; Zander, A.R. [Universitaetskrankenhaus Eppendorf, Hamburg (Germany). Zentrum fuer Knochenmarktransplantation

    1999-10-01

    Purpose: Evaluation of digitized chest X-ray for the detection of pulmonary infiltrations in bone marrow transplant patients during aplasia. Methods: Digitized chest X-rays of 40 patients (21 female, 19 male) with 'Fever of unknown origin' (FUO) were evaluated concerning radiological signs of pulmonary infiltrations and correlated to clinical findings, blood chemistry, microbiology and bronchoscopy. Additionally, an individual risk profile was established. Results: In 11/40 patients pulmonary infiltrations were detected in digitized chest X-rays (group 1). 10/11 developed an infectious pulmonary infiltration. 29/40 patients developed no pulmonary infiltration (group 2). When fever increased for the first time (initial chest X-ray) a sensitivity, specificity, positive and negative predictive value of 46%, 86%, 56%, 81% and for the chest X-rays in process of 61%, 79%, 68% and 73% was found. C-reactive protein and temperature increase occured statistically significantly earlier (p<0.05) in group 1 compared to group 2. The average latency of digital chest X-rays in comparison to c-reactive protein and temperature increase was 6 days. The incidence of risk factors was significantly higher in group 1 in comparison to group 2 (p<0.05). Conclusion: Digitized chest X-rays are not a reliable method for primary detection of pulmonary infiltrations after bone marrow transplantation. Individual risk factors have to be taken into consideration to indicate further diagnostic methods such as computed tomography at an earlier time. (orig.) [German] Ziel: Wertigkeit der digitalen Thoraxaufnahme bei der Detektion pulmonaler Infiltrate bei knochenmarktransplantierten Patienten in der Aplasie. Methoden: Digitale Thoraxaufnahmen von 40 Patienten (21 Frauen, 19 Maenner) in Aplasie mit Fieber unklarer Genese wurden nach Zeichen pulmonaler Infiltrate ausgewertet und mit klinischen, laborchemischen, mikrobiologischen und bronchoskopischen Befunden korreliert. Zusaetzlich wurde ein

  3. Bamboo spine – X-ray findings of ankylosing spondylitis revisited

    Directory of Open Access Journals (Sweden)

    Antoinette Reinders

    2012-09-01

    Full Text Available Ankylosing spondylitis is a debilitating disease that is one of the seronegative spondylarthropathies, affecting more males than females in the proportion of about 6:1 in the age group 15 - 35 years of age. Early radiographic findings include bilateral sacro-iliitis and early axial (lower lumbar spine ankylosis. Typical X-ray findings are florid spondylitis (Romanus lesions, florid diskitis (Andersson lesions, early axial ankylosis, enthesitis, syndesmophytes and insufficiency fractures. Typical radiological abnormalities are pointed out on conventional X-rays and reviewed for early diagnosis and prompt treatment of patients at risk.

  4. Objective quantification of pulmonary effects in X-ray chest images; Quantificacao objetiva das sequelas pulmonares em imagens de raios-X de torax

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Marcela de; Giacomini, Guilherme; Alvarez, Matheus; Pereira, Paulo M.C.; Ribeiro, Sergio M.; Pina, Diana R. de [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Botucatu, SP (Brazil)

    2016-07-01

    Tuberculosis (TB) is an infectious lung disease of great concern worldwide. Even after treatment, TB leaves pulmonary sequelae that compromise the quality of life of patients. The exam of diagnostic imaging done more frequently is the X-ray chest. The evaluation of pulmonary involvement of these patients is performed visually by the radiologist. The detection and quantification aided by computer systems are of great importance for the more accurate assessment of pulmonary involvement. The objective of this study was to evaluate computationally the reduction of lung damage in X-ray of chest in patients treated with two different medication regimens. (author)

  5. Can routine trauma bay chest x-ray be bypassed with an extended focused assessment with sonography for trauma examination?

    Science.gov (United States)

    Soult, Michael C; Weireter, Leonard J; Britt, Rebecca C; Collins, Jay N; Novosel, Timothy J; Reed, Scott F; Britt, L D

    2015-04-01

    The objective of this study was to investigate the feasibility of using ultrasound (US) in place of portable chest x-ray (CXR) for the rapid detection of a traumatic pneumothorax (PTX) requiring urgent decompression in the trauma bay. All patients who presented as a trauma alert to a single institution from August 2011 to May 2012 underwent an extended focused assessment with sonography for trauma (FAST). The thoracic cavity was examined using four-view US imaging and were interpreted by a chief resident (Postgraduate Year 4) or attending staff. US results were compared with CXR and chest computed tomography (CT) scans, when obtained. The average age was 37.8 years and 68 per cent of the patients were male. Blunt injury occurred in 87 per cent and penetrating injury in 12 per cent of activations. US was able to predict the absence of PTX on CXR with a sensitivity of 93.8 per cent, specificity of 98 per cent, and a negative predictive value of 99.9 per cent compared with CXR. The only missed PTX seen on CXR was a small, low anterior, loculated PTX that was stable for transport to CT. The use of thoracic US during the FAST can rapidly and safely detect the absence of a clinically significant PTX. US can replace routine CXR obtained in the trauma bay and allow more rapid initiation of definitive imaging studies.

  6. Chest x ray films from construction workers: International Labour Office (ILO 1980) classification compared with routine readings.

    Science.gov (United States)

    Albin, M; Engholm, G; Fröström, K; Kheddache, S; Larsson, S; Swantesson, L

    1992-12-01

    The extent of agreement between International Labour Office (ILO) and clinical readings of chest x ray films from construction workers was studied. From a survey of 5898 workers 258 subjects with a profusion of small opacities of > or = 1/1 and a stratified sample of subjects with profusion ILO profusion category > or = 1/1 were clinically recorded as non-normal for the parenchyma. The proportion of films recorded as pneumoconiotic (or possibly so) was especially low for irregular opacities (22%), but increased with the profusion category (both rounded and irregular) as well as with the size of rounded opacities (p 3/11, q 12/25, r 3/4). Only with the profusion category > or = 2/1 were most of the films recorded as pneumoconiotic. The specificity and sensitivity were highest in the geographical areas where a few clinical readers had assessed many films each. The proportion of false negative clinical reports was low for circumscribed pleural thickening of the chest wall (9%) and diaphragmatic pleural thickening (6%). For calcified pleural changes and for the combination of diffuse pleural thickening and obliteration of the costophrenic angle, false negative reports were absent. The present study shows an unsatisfactory sensitivity for clinical compared with ILO readings as a means for screening the parenchyma of workers with a risk of pneumoconiosis.

  7. FINDINGS OF CHEST RADIOGRAPH AND SPIRAL COMPUTED TOMOGRAPHY IN SWYER-JAMES SYNDROME

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective To evaluate the value of X-ray and spiral computed tomography (SCT) in the diagnosis of SwyerJames syndrome (SJS).Methods A total of 28 patients, 12 males and 16 females, were studied retrospectively. Ages ranged from 11 to 57 years, the mean age was 32 years. All patients underwent inspiratory chest X-ray films, 5 with expiratory chest films and 1 with bronchogram. Furthermore, inspiratory and expiratory SCT scans were performed. The SCT findings were analyzed and compared with X-ray films.Results SCT demonstrated 56 lobes with hyperlucency and diminished vascularity. The size of 51 lobes were smaller and 5 were normal. X-ray films showed that hyperlucency was only in 29 lobes, in which 19 lobes were smallsized and the other 10 lobes normal. There were 56 lobes with air-trapping on expiratory SCT scans, but only 5 lobes with air-trapping on expiratory X-ray films. Bronchogram in 1 case demonstrated bronchiectasis and bronchiolitis obliterans. SCT showed 24 patients with bronchiectasis, 9 patients with tuberculosis, 10 patients with bronchiolitis, and 2 with segmental collapse. Conclusion SCT scan is superior to chest radiography in the diagnosis and differential diagnosis of SJS.

  8. Extravascular lung water index measurement in critically ill children does not correlate with a chest x-ray score of pulmonary edema.

    NARCIS (Netherlands)

    Lemson, J.; Die, L. van; Hemelaar, A.E.A.; Hoeven, J.G. van der

    2010-01-01

    INTRODUCTION: Extravascular lung water index (EVLWI) can be measured at the bedside using the transpulmonary thermodilution technique (TPTD). The goal of this study was to compare EVLWI values with a chest x-ray score of pulmonary edema and markers of oxygenation in critically ill children. METHODS:

  9. Optimization of exposure parameters for pediatric chest x-ray imaging

    Science.gov (United States)

    Park, Hye-Suk; Kim, Ye-Seul; Kim, Hee-Joung

    2012-03-01

    The pediatric patients are more susceptible to the effects of ionizing radiation than adults. Pediatric patients are smaller, more radiosensitive than adult patients and many cannot stand unassisted. Their characteristics affect the method of imaging projection and how dose is optimized. The purpose of this study was to investigate the effect of various technical parameters for the dose optimization in pediatric chest radiological examinations by evaluating effective dose and effective detective quantum efficiency (eDQE) including the scatter radiation from the object, the blur caused by the focal spot, geometric magnification and detector characteristics. For the tube voltages ranging from 40 to 90 kV in 10 kV increments at the focus-to-detector distance of 100, 110, 120, 150, 180 cm, the eDQE was evaluated at same effective dose. The results showed that the eDQE was largest at 60 kVp without and with an anti-scatter grid. Especially, the eDQE was considerably higher without the use of an anti-scatter grid on equivalent effective dose. This indicates that the reducing the scatter radiation did not compensate for the loss of absorbed effective photons in the grid. When the grid is not used the eDQE increased with increasing focus-to-detector distance because of the greater effective modulation transfer function (eMTF) with the lower focal spot blurring. In conclusion, for pediatric patients, the amount of scattered radiation is less, and the amount of grid attenuation increased unnecessary radiation dose.

  10. Complete blood counts, liver function tests, and chest x-rays as routine screening in early-stage breast cancer: value added or just cost?

    Science.gov (United States)

    Louie, Raphael J; Tonneson, Jennifer E; Gowarty, Minda; Goodney, Philip P; Barth, Richard J; Rosenkranz, Kari M

    2015-11-01

    Current National Comprehensive Cancer Network guidelines for breast cancer staging include pre-treatment complete blood count (CBC) and liver function tests (LFT) to screen for occult metastatic disease. To date, the relevance of these tests in detecting metastatic disease in asymptomatic women with early-stage breast cancer (Stage I/II) has not been demonstrated. Although chest x-rays are no longer recommended in the NCCN guidelines, many centers continue to include this imaging as part of their screening process. We aim to determine the clinical and financial impact of these labs and x-rays in the evaluation of early-stage breast cancer patients. A single institution IRB-approved retrospective chart review was conducted of patients with biopsy-proven invasive breast cancer treated from January 1, 2005–December 31, 2009. We collected patient demographics, clinical and pathologic staging, chest x-ray, CBC, and LFT results at the time of referral. Patients were stratified according to radiographic stage at the time of diagnosis. We obtained Medicare reimbursement fees for cost analysis. From 2005 to 2009, 1609 patients with biopsy-proven invasive breast cancer were treated at our institution. Of the 1082 patients with radiographic stage I/II disease, 27.3 % of patients had abnormal CBCs. No additional testing was performed to evaluate these abnormalities. In the early-stage population, 24.7 % of patients had elevated LFTs, resulting in 84 additional imaging studies. No metastatic disease was detected. The cost of CBC, LFTs and chest x-rays was $110.20 per patient, totaling $106,410.99. Additional tests prompted by abnormal results cost $58,143.30 over the five-year period. We found that pre-treatment CBCs, LFTs, and chest x-rays did not improve detection of occult metastatic disease but resulted in additional financial costs. Avoiding routine ordering of these tests would save the US healthcare system $25.7 million annually.

  11. Finding Rare AGN: X-ray Number Counts of Chandra Sources in Stripe 82

    CERN Document Server

    LaMassa, Stephanie M; Glikman, Eilat; Cappelluti, Nico; Civano, Francesca; Comastri, Andrea; Treister, Ezequiel; Arifin,; Boehringer, Hans; Cardamone, Carie; Chon, Gayoung; Kephart, Miranda; Murray, Stephen S; Richards, Gordon; Ross, Nic; Rozner, Joshua S; Schawinski, Kevin

    2012-01-01

    We present the first results of a wide area X-ray survey within the Sloan Digital Sky Survey (SDSS) Stripe 82, a 300 deg$^2$ region of the sky with a substantial investment in multi-wavelength coverage. We analyzed archival {\\it Chandra} observations that cover 7.5 deg$^2$ within Stripe 82 ("Stripe 82 ACX"), reaching 4.5$\\sigma$ flux limits of 7.9$\\times10^{-16}$, 3.4$\\times10^{-15}$ and 1.8$\\times10^{-15}$ erg s$^{-1}$ cm$^{-2}$ in the soft (0.5-2 keV), hard (2-7 keV) and full (0.5-7 keV) bands, to find 774, 239 and 1118 X-ray sources, respectively. Three hundred twenty-one sources are detected only in the full band and 9 sources are detected solely in the soft band. Utilizing data products from the {\\it Chandra} Source Catalog, we construct independent Log$N$-Log$S$ relationships, detailing the number density of X-ray sources as a function of flux, which show general agreement with previous {\\it Chandra} surveys. We compare the luminosity distribution of Stripe 82 ACX with the smaller, deeper CDF-S + E-CDFS...

  12. Teratoma do mediastino simulando derrame pleural no estudo radiológico do tórax Mediastinal teratoma mimicking pleural effusion on chest X-rays

    Directory of Open Access Journals (Sweden)

    Miguel Angelo Martins de Castro Júnior

    2007-02-01

    Full Text Available Teratomas mediastinais representam 8 a 13% dos tumores nesta região. Uma paciente de 27 anos apresentou-se com dor torácica e dispnéia de evolução arrastada. O radiograma de tórax revelou opacidade quase total do hemitórax direito, levando à suspeita de derrame pleural. A tomografia de tórax evidenciou coleção pleural heterogênea, de contornos regulares (10,1 x 11,7 cm, nos dois terços inferiores do hemitórax direito, sem envolvimento de estruturas adjacentes. Na toracotomia exploradora, pela hipótese de teratoma cístico benigno do mediastino, realizou-se ressecção total da lesão, com boa evolução pós-operatória. A apresentação atípica e grande crescimento do tumor dificultaram o diagnóstico pré-operatório.Teratomas account for 8-13% of all mediastinal tumors. A 27-year-old patient presented with chest pain and dyspnea of prolonged evolution. A chest X-ray revealed near total opacification of the right hemithorax. On a tomography scan of the chest, a collection of heterogeneous fluid, with irregular borders and 10.1 x 11.7 cm in size, was seen in the pleura of the lower two-thirds of the right hemithorax but was not encroaching on any of the adjacent structures. Based on the hypothesis that these findings represented a benign mediastinal teratoma, an exploratory thoracotomy was performed, during which such a teratoma was found and completely excised. The post-operative evolution was favorable. The atypical presentation and considerable growth of the tumor hindered the pre-operative diagnosis.

  13. Chest radiographic findings in acute paraquat poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Na, Gyeong Gyun; Lee, Mi Sook; Kim, Hee Jun; Sun, In O [Presbyterian Medical Center, Jeonju (Korea, Republic of)

    2016-01-15

    To describe the chest radiographic findings of acute paraquat poisoning. 691 patients visited the emergency department of our hospital between January 2006 and October 2012 for paraquat poisoning. Of these 691, we identified 56 patients whose initial chest radiographs were normal but who developed radiographic abnormalities within one week. We evaluated their radiographic findings and the differences in imaging features based on mortality. The most common finding was diffuse consolidation (29/56, 52%), followed by consolidation with linear and nodular opacities (18/56, 32%), and combined consolidation and pneumomediastinum (7/56, 13%). Pleural effusion was noted in 17 patients (30%). The two survivors (4%) showed peripheral consolidations, while the 54 patients (96%) who died demonstrated bilateral (42/54, 78%) or unilateral (12/54, 22%) diffuse consolidations. Rapidly progressing diffuse pulmonary consolidation was observed within one week on follow-up radiographs after paraquat ingestion in the deceased, but the survivors demonstrated peripheral consolidation.

  14. Chest x-ray

    Science.gov (United States)

    ... Test will Feel There is no discomfort. The film plate may feel cold. Why the Test is ... of Medicine, Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also ...

  15. Chest X-Ray

    Medline Plus

    Full Text Available ... About Us News Physician Resources Professions Site Index A-Z Spotlight Recently posted: Anal Cancer Facet Joint ... dot org! Hello, I’m Dr. Geoffrey Rubin, a radiologist at Duke University in Durham, North Carolina. ...

  16. Chest X-Ray

    Medline Plus

    Full Text Available ... Site Index A-Z Spotlight Recently posted: Anal Cancer Facet Joint Block Video: CT of the Heart ... Therapy Video: CT of the Sinuses Video: Colorectal Cancer Screening Radiology and You Sponsored by Image/Video ...

  17. Pulmonary involvement in patients presenting with extra-pulmonary tuberculosis: thinking beyond a normal chest x-ray

    Directory of Open Access Journals (Sweden)

    Herath S

    2014-03-01

    Full Text Available INTRODUCTION: Recognition of pulmonary involvement in extra-pulmonary tuberculosis (TB may be an important public health issue, as smear-negative pulmonary TB is responsible for about 17% of new infections. Pulmonary TB can be present despite a normal chest x-ray (CXR, even in human immunodeficiency virus (HIV–negative patients. In this retrospective clinical audit, we reviewed a case series of HIV-negative patients with extra-pulmonary tuberculosis to identify the proportion with concurrent pulmonary TB despite an unremarkable CXR. METHODS: Clinical notes, microbiology results and CXR reports were reviewed from consecutive patients treated at Auckland City Hospital for extra-pulmonary TB from January 2007 to July 2010. RESULTS: Of the sample of 103 patients with extra-pulmonary TB, the majority of patients were born in an Asian country (n=70; 68%. The commonest presentation of extra-pulmonary TB was lymphadenopathy (n=51; 50%, followed by pleural (n=24; 23% and bone (n=6; 6% disease. Extra-pulmonary TB was diagnosed by biopsy or excision of the extra-pulmonary site in the majority (n=74; 72%, and by sputum testing alone in 26 (25%. The majority had CXR abnormalities (n=76; 74%. In the group with a normal CXR (n=27, 55% (n=15 had sputum cultures performed. In total, 18% (n=5 of patients with extra-pulmonary TB and a normal CXR had pulmonary TB, of whom two were smear positive. DISCUSSION: In patients with extra-pulmonary TB, sputum testing should be considered to detect concurrent pulmonary TB even if a CXR is normal, especially in immunosuppressed or symptomatic patients. This may aid diagnosis and determine infectivity and consequent public health action.

  18. Routine Chest X-ray: Still Valuable for the Assessment of Left Ventricular Size and Function in the Era of Super Machines?

    Directory of Open Access Journals (Sweden)

    Maria-Aurora Morales

    2012-01-01

    Full Text Available Objectives: The development of technologically advanced, expensive techniques has progressively reduced the value of chest X-ray in clinical practice for the assessment of left ventricular (LV dilatation and dysfunction. Although controversial data are reported on the role of this widely available technique in cardiac assessment, it is known that the cardio-thoracic ratio is predictive of risk of progression in the NYHA Class, hospitalization, and outcome in patients with LV dysfunction. This study aimed to evaluate the reliability of the transverse diameter of heart shadow [TDH] by chest X-ray for detecting LV dilatation and dysfunction as compared to Magnetic Resonance Imaging (MRI performed for different clinical reasons. Materials and Methods: In 101 patients, TDH was measured in digital chest X-ray and LV volumes and ejection fraction (EF by MRI, both exams performed within 2 days. Results: A direct correlation between TDH and end-diastolic volumes (r = .75, P150 mL (sensitivity: 82%, specificity: 69%; in males a cut-off value of 15.5 mm identified LV end-diastolic volumes >210 mL (sensitivity: 84%; specificity: 72%. A negative relation was found between TDH and LVEF (r = -.54, P<0.0001. The above cut-off values of TDH discriminated patients with LV systolic dysfunction - LVEF <35% (sensitivity and specificity: 67% and 57% in females; 76% and 59% in males, respectively. Conclusions: Chest X-ray may still be considered a reliable technique in predicting LV dilatation by the accurate measurement of TDH as compared to cardiac MRI. Technologically advanced, expensive, and less available imaging techniques should be performed on the basis of sound clinical requests.

  19. The effect of dexamethasone on respirator-dependent very-low-birth-weight infants is best predicted by chest X-ray

    Energy Technology Data Exchange (ETDEWEB)

    Schrod, L.; Neuhaus, T. [Dept. of Paediatrics, Univ. of Wuerzburg (Germany); Horwitz, A.E. [Dept. of Radiology/Paediatric Radiology, Univ. of Wuerzburg (Germany); Speer, C.P. [Dept. of Neonatology, Univ. of Tuebingen (Germany)

    2001-05-01

    Background. Chronic lung disease (CLD) in premature infants shows a variable clinical course with different radiological manifestations. Objective. To evaluate the correlation between parameters of transmembrane permeability [albumin/secretory component (SC)] and oxidative stress [malondialdehyde (MDA)/SC] in tracheal aspirate fluid (TAF) and radiological findings with the effect of a 5-day course of dexamethasone (0.5 mg/kg per day). Materials and methods. Fifty ventilator-dependent premature infants with birth weights < 1,500 g (gestational ages 23-31 weeks) and radiological signs of early chronic lung disease (CLD) were treated with dexamethasone at day of life 5-27 (median 10 days) because of respiratory deterioration. TAF was collected serially. Chest X-rays taken before and 8-10 days after dexamethasone were scored for changes of opacification, consolidation and hyperinflation/emphysema, and classified into three groups. Results. Twenty-four infants had a positive response to dexamethasone, defined as a reduction of the ventilation index FiO{sub 2} x mean airway pressure > 40 % at day 5, compared to pretreatment values. About 80 % of the responders showed homogeneous lung opacification on chest X-ray, reflecting leaky lung syndrome. In contrast, seven of eight infants with predominantly emphysema on radiology were non-responders; 80 % of infants with a mixed radiological picture characterized by predominance of consolidations alternating with regions of emphysema were also non-responders. Ratios of albumin/SC and MDA/SC in TAF decreased significantly within 3 days after the onset of dexamethasone. However, MDA/SC was persistently higher in non-responders compared to responders. Opaque lungs were largely improved by dexamethasone, in contrast to streaky or patchy consolidations and emphysema. In a logistic regression model, radiographic classification was the most important factor influencing the response to dexamethasone with a positive predictive value of 86

  20. Magnetic Resonance Urography and X-ray Urography Findings of Congenital Megaureter

    Institute of Scientific and Technical Information of China (English)

    Tian-ran Li; Xiang-ke Du; Tian-Iong Huo

    2011-01-01

    Objective To observe the imaging findings of congenital megaureter in order to enhance the understanding of this disease.Methods Image data of 5 patients with congenital megaureter and 2 misdiagnosed patients were analyzed, and image findings of congenital megaureter were summarized. Elscint Prestig 2.0T superconductive magnetic resonance urography (MRU) with conventional sequence (spin-echo, T1WI 560 ms/16 ms; fast spin-echo, T2WI 9600 ms/96 ms) was performed. Raw data were acquired with fast spin-echo sequence from heavy T2-weighted image (9600 ms/120 ms). Post-processing method of MRU was the maximum intensity projection with three-dimensional reconstruction in the workstation. Intravenous pyelography (IVP) was conducted, in which X-ray films were taken 7 minutes, 15 minutes, and 30 minutes after injecting contrast agent, except that in 2 patients the films were taken delayed at 60 and 90 minutes. X-ray retrograde pyelography was performed on 2 patients, successful in one but failed in the other. Results The dilated ureter showed hypointensity on T1-weighted images and hyperintensity on T2-weighted images in conventional MRI. The mass wall was intact, uniform in thickness, and showing hypointensity on T1-weighted and T2-weighted images. The MRH images showed a retroperitoneal mass appearing as an elongated tubular cystic structure spreading from kidney to bladder. MRH also revealed dilated calices and renal pelvis, pelviureteric obstruction, and renal duplication. The main signs of congenital megaureter in X-urography was significant dilatation of ureter, or normal renal pelvis with ureter dilatation,hydronephrosis, deformity, and displacement.Conclusions MRU with X-urography could visualize the characteristics of congenital megaureter, including the dilation of renal pelvis and ureter, calculi, urinary tract duplication, and stenosis location. The two techniques can complement each other in disease diagnosis and provide more detailed information for

  1. Scientists Find X Rays from Stellar Winds That May Play Significant Role in Galactic Evolution

    Science.gov (United States)

    2001-09-01

    Colorful star-forming regions that have captivated stargazers since the advent of the telescope 400 years ago contain gas thousands of times more energetic than previously recognized, powered by colliding stellar winds. This multimillion-degree gas radiated as X rays is one of the long-sought sources of energy and elements in the Milky Way galaxy's interstellar medium. A team led by Leisa Townsley, a senior research associate in astronomy and astrophysics at Penn State University, uncovered this wind phenomenon in the Rosette Nebula, a stellar nursery. With the Chandra X-ray Observatory, the team found that the most massive stars in the nebula produce winds that slam into each other, create violent shocks, and infuse the region with 6-million-degree gas. The findings are presented in Washington, D.C., today at a conference entitled "Two Years of Science with Chandra." "A ghostly glow of diffuse X-ray emission pervades the Rosette Nebula and perhaps many other similar star-forming regions throughout the Galaxy," said Townsley. "We now have a new view of the engine lighting the beautiful Rosette Nebula and new evidence for how the interstellar medium may be energized." Townsley and her colleagues created a striking X-ray panorama of the Rosette Molecular Cloud from four images with Chandra's Advanced CCD Imaging Spectrometer. This is a swath of the sky nearly 100 light years across sprayed with hundreds of X-ray-emitting young stars. In one corner of the Rosette Molecular Cloud lies the Rosette Nebula, called an "H II region" because the hydrogen gas there has been stripped of its electrons due to the strong ultraviolet radiation from its young stars. This region, about 5,000 light years away in the constellation Monoceros, the Unicorn, has long been a favorite among amateur astronomers. The wispy, colorful display is visible with small telescopes. The Chandra survey reveals, for the first time, 6-million-degree gas at the center of the Rosette Nebula, occupying a

  2. Reliable quantitative score for grading chest X-ray using the dynamic of blood cell count in adult asthma

    Directory of Open Access Journals (Sweden)

    Al-Said A. Haffor

    2015-04-01

    Based on the results of the present study it can be concluded that monitoring CBC parameters can be an objective estimate of the S–K score for CXR in order to classify the severity of asthma using an objective numerical value to assess patients’ treatment follow up, without the need for X-ray equipment setup.

  3. A pilot study evaluating erect chest imaging in children, using the Lodox Statscan digital X-ray machine

    OpenAIRE

    2009-01-01

    ABSTRACT Background: Chest radiography accounts for a significant proportion of ionising radiation in children. The radiation dose of radiographs performed on the Lodox Statscan system has been shown to be lower than that of a computed radiography (CR) system. The role of the Lodox Statscan (hereafter referred to as the Statscan) in routine erect chest radiography in children has not been evaluated. Objective: To evaluate the image quality and diagnostic accuracy of erect paedi...

  4. Detection of metastases in breast cancer patients. Comparison of FDG PET with chest X-ray, bone scintigraphy and ultrasound of the abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Dose-Schwarz, J.; Mahner, S.; Schirrmacher, S.; Mueller, V. [Klinik und Poliklinik fuer Gynaekologie, Universitaetsklinikum Hamburg-Eppendorf (Germany); Jenicke, L.; Brenner, W. [Klinik fuer Nuklearmedizin, Universitaetsklinikum Hamburg-Eppendorf (Germany); Habermann, C.R. [Klinik fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Hamburg-Eppendorf (Germany)

    2008-07-01

    Distant metastases at primary diagnosis are a prognostic key factor in breast cancer patients and play a central role in therapeutic decisions. To detect them, chest X-ray, abdominal ultrasound, and bone scintigraphy are performed as standard of care in Germany and many centers worldwide. Although FDG PET detects metastatic disease with high accuracy, its diagnostic value in breast cancer still needs to be defined. The aim of this study was to compare the diagnostic performance of FDG PET with conventional imaging. Patients, methods: a retrospective analysis of 119 breast cancer patients who presented for staging was performed. Whole-body FDG-PET (n = 119) was compared with chest X-ray (n = 106) and bone scintigraphy (n = 95). Each imaging modality was independently assessed and classified for metastasis (negative, equivocal and positive). The results of abdominal ultrasound (n = 100) were classified as negative and positive according to written reports. Imaging results were compared with clinical follow-up including follow-up imaging procedures and histopathology. Results: FDG-PET detected distant metastases with a sensitivity of 87.3% and a specificity of 83.3%. In contrast, the sensitivity and specificity of combined conventional imaging procedures was 43.1% and 98.5%, respectively. Regarding so-called equivocal and positive results as positive, the sensitivity and specificity of FDG-PET was 93.1% and 76.6%, respectively, compared to 61.2% and 86.6% for conventional imaging. Regarding different locations of metastases the sensitivity of FDG PET was superior in the detection of pulmonary metastases and lymph node metastases of the mediastinum in comparison to chest X-ray, whereas the sensitivity of FDG PET in the detection of bone and liver metastases was comparable with bone scintigraphy and ultrasound of the abdomen. Conclusions: FDG-PET is more sensitive than conventional imaging procedures for detection of distant breast cancer metastases and should be

  5. Evaluation of the entrance skin dose due to paediatric chest X-rays examinations carried out at a great hospital in Rio de Janeiro city

    Energy Technology Data Exchange (ETDEWEB)

    Mohamadain, K.E.M. [Sudan Univ. of Science and Technology, Khartoum (Sudan). Faculty of Sciences. Physics Dept.; Azevedo, A.C.P. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Faculdade de Medicina. Dept. de Radiologia; Rosa, L.A.R. da; Mota, H.C. [Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ (Brazil). Dept. de Fisica Medica; Goncalves, O.D. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Fisica. Dept. de Fisica Nuclear; Guebel, M.R.N. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Pediatria e Puericultura Martagao Gesteira

    2001-07-01

    A dosimetric survey in paediatric radiology is currently being carried out at the paediatric unit of a great hospital in Rio de Janeiro city, aiming the assessment of patient doses and image quality. The aim of this work was to estimate the entrance skin dose for frontal and lateral chest X-rays exposure to paediatric patients. Three examination techniques were investigated, namely PA, AP and lateral positions. For entrance skin dose evaluation, two different TL dosimeters were used, namely LiF:Mg,Ti and CaSO4:Dy. The age intervals considered were 0-1 year, 1-5 years, 5-10 years and 10-15 years. The results obtained with both dosimeters are similar and the entrance skin dose values evaluated for the different age intervals considered are compared with previous values found in Brazil and also in Europe. (author)

  6. Prevalence of Radiologic Findings in Patients with Blunt Chest Trauma in Isfahan

    Directory of Open Access Journals (Sweden)

    M. Haghighi

    2008-01-01

    Full Text Available Background/Objective: Chest trauma due to its vital organs can be very dangerous and lethal. Our country has the first grade of accidents in the word, so rapid diagnosis and treatment in patients with chest trauma is necessary. One cost benefit and available imaging modality in each Region of our country is X-ray."nCXR interpretation needs to knowledge about prevalence of abnormal Radiologic findings and their accuracy. Therefore, it is necessary to perform a study about the rate of CXR abnormal findings in patients with blunt chest trauma."nPatients and Methods: In this descriptive and prospective study, CXR of patients with blunt chest trauma that admitted in Alzahra and Kashani hospitals studied and percent of vital radiologic findings prevalence determined."nResults: The final results were as below:"n1- Rib FX (18.5% (143, 2- Hemothorax (13.6% (105, 3- Pneumothorax (11.8% (91, 4- Sub cutaneous emphysema (10.2% (79, 5- Lung laceration (8.1% (63, 6- Mediastinal winding (6.4% (50, 7- Clavicular and sternal FX (5.8% (44, 8- Pneumo mediastinum (4.1% (32, 9- spinal FX (3.5% (27, 10- Great vessels injury signs (1.4% (11."nConclusion: According to above results, accurate investigation of CXR, helps physician and radiologist to find any threatened finding, so determination of next step as clinical follow up or spiral CT, angiography or surgery; accordingly.

  7. [The use of chest X-rays for surveillance of bacterial pneumonias in children in Latin America].

    Science.gov (United States)

    Lagos, Rosanna; di Fabio, José Luis; Moënne, Karla; Muñoz M, Alma; Wasserman, Steven; de Quadros, Ciro

    2003-05-01

    The Division of Vaccines and Immunization of the Pan American Health Organization (PAHO) is promoting epidemiological surveillance of bacterial pneumonias in children in Latin America in order to generate scientific evidence to support future decisions concerning using vaccines to control such pneumonias in the countries of the Region of the Americas. The diagnosis of these diseases rarely includes bacteriological documentation of the causative agent. Therefore, studies of this type that are carried out around the world accept radiological images of alveolar consolidation as a confirmatory criterion for a presumptively bacterial pneumonia. This piece examines the theoretical rationale and requirements for using thorax radiology as an instrument for epidemiological surveillance of bacterial pneumonias. The piece also summarizes the activities carried out during 2 years of joint efforts between the Center for Vaccine Development (Centro para Vacunas en Desarrollo) of Chile and PAHO's Division of Vaccines and Immunization. During those 2 years, the two groups encouraged the epidemiological study of bacterial pneumonias in Latin American children, using internationally accepted criteria and definitions as well as tools and practical solutions adapted to the reality of the Region of the America. The activities carried out so far show both the need for and the feasibility of standardizing the interpretation of chest radiographs so that they can be used in epidemiological studies.

  8. Pulmonary embolism findings on chest radiographs and multislice spiral CT

    Energy Technology Data Exchange (ETDEWEB)

    Coche, Emmanuel; Goncette, Louis [Department of Radiology, Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Avenue Hippocrate 10, 1200, Brussels (Belgium); Verschuren, Franck [Department of Intensive Care and Emergency Medicine, Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Avenue Hippocrate 10, 1200, Brussels (Belgium); Hainaut, Philippe [Department of Internal Medicine, Cliniques Universitaires Saint-Luc, Universite Catholique de Louvain, Avenue Hippocrate 10, 1200, Brussels (Belgium)

    2004-07-01

    Multislice spiral CT is becoming an increasingly important tool for diagnosing pulmonary embolism. However, in many instances, a chest radiograph is usually performed as a first-line examination. Many parenchymal, vascular, and other ancillary findings may be observed on both imaging modalities with a highly detailed depiction of abnormalities on multislice CT. A comprehensive review of chest radiograph findings is presented with side-by-side correlations of CT images reformatted mainly in the frontal plane. (orig.)

  9. Pulmonary embolism findings on chest radiographs and multislice spiral CT.

    Science.gov (United States)

    Coche, Emmanuel; Verschuren, Franck; Hainaut, Philippe; Goncette, Louis

    2004-07-01

    Multislice spiral CT is becoming an increasingly important tool for diagnosing pulmonary embolism. However, in many instances, a chest radiograph is usually performed as a first-line examination. Many parenchymal, vascular, and other ancillary findings may be observed on both imaging modalities with a highly detailed depiction of abnormalities on multislice CT. A comprehensive review of chest radiograph findings is presented with side-by-side correlations of CT images reformatted mainly in the frontal plane.

  10. INTEGRAL finds renewed X-ray activity of the Neutron star X-ray transient SAX J1750.8-2900

    DEFF Research Database (Denmark)

    Sanchez-Fernandez, Celia; Chenevez, Jérôme; Kuulkers, Erik;

    2015-01-01

    seconds. The source is not detected with IBIS/ISGRI on September 13 with 3-sigma upper limits of about 5 and 8 mCrab in the 18-40 keV and 40-100 keV bands, respectively (12.6 ksec exposure). Similar observations about 5 days earlier (on UT 8 September 2015 13:52-17:34; 12.6 ksec exposure) did not reveal......, 3181). The JEM-X 3-10 keV and 10-25 keV fluxes during our observations are 32+/-3 mCrab and 16+/-6 mCrab respectively. A Type I X-ray burst from SAX J1750.8-2900 was detected during these observations, on UT 13 September 2015 20:51, with a peak flux of 2.3+/-0.2 Crab (3-25 keV) and a duration of 17...... the source with 3-sigma upper limits of 7 (3-10 keV) and 15 mCrab (10-25 keV). We encourage further observations of SAX J1750.8-2900 at X-rays and other wavelengths....

  11. Development of Portable Digital Radiography System with a Device for Monitoring X-ray Source-Detector Angle and Its Application in Chest Imaging

    Directory of Open Access Journals (Sweden)

    Tae-Hoon Kim

    2017-03-01

    Full Text Available This study developed a device measuring the X-ray source-detector angle (SDA and evaluated the imaging performance for diagnosing chest images. The SDA device consisted of Arduino, an accelerometer and gyro sensor, and a Bluetooth module. The SDA values were compared with the values of a digital angle meter. The performance of the portable digital radiography (PDR was evaluated using the signal-to-noise (SNR, contrast-to-noise ratio (CNR, spatial resolution, distortion and entrance surface dose (ESD. According to different angle degrees, five anatomical landmarks were assessed using a five-point scale. The mean SNR and CNR were 182.47 and 141.43. The spatial resolution and ESD were 3.17 lp/mm (157 μm and 0.266 mGy. The angle values of the SDA device were not significantly difference as compared to those of the digital angle meter. In chest imaging, the SNR and CNR values were not significantly different according to the different angle degrees. The visibility scores of the border of the heart, the fifth rib and the scapula showed significant differences according to different angles (p < 0.05, whereas the scores of the clavicle and first rib were not significant. It is noticeable that the increase in the SDA degree was consistent with the increases of the distortion and visibility score. The proposed PDR with a SDA device would be useful for application in the clinical radiography setting according to the standard radiography guidelines.

  12. HRCT findings of chest complications in patients with leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Nobuyuki; Matsumoto, Tsuneo; Miura, Gouji; Emoto, Takuya; Matsunaga, Naofumi [Department of Radiology, Yamaguchi University School of Medicine (Japan)

    2002-06-01

    High-resolution CT (HRCT) findings of several chest complications occurring in leukemic patients were reviewed. Although most entities show non-specific HRCT findings including ground-glass opacity and air-space consolidation, characteristic findings are observed in several pulmonary complications including Pneumocystis carinii pneumonia, fungal infections, miliary tuberculosis, leukemic infiltration, pulmonary edema, bronchiolitis obliterans, and bronchiolitis obliterans organizing pneumonia. A combination of these characteristic HRCT findings and the information obtained from the clinical setting may help in achieving a correct diagnosis of chest complications occurring in leukemic patients. (orig.)

  13. Performance of ultralow-dose CT with iterative reconstruction in lung cancer screening: limiting radiation exposure to the equivalent of conventional chest X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Huber, Adrian [University Hospital Inselspital Bern, Department of Diagnostic, Interventional and Paediatric Radiology, Bern (Switzerland); University Hospital Pitie-Salpetriere, Department of Polyvalent and Oncological Radiology, Paris (France); Landau, Julia; Buetikofer, Yanik; Leidolt, Lars; Brela, Barbara; May, Michelle; Heverhagen, Johannes; Christe, Andreas [University Hospital Inselspital Bern, Department of Diagnostic, Interventional and Paediatric Radiology, Bern (Switzerland); Ebner, Lukas [University Hospital Inselspital Bern, Department of Diagnostic, Interventional and Paediatric Radiology, Bern (Switzerland); Duke University Medical Center, Department of Radiology, Durham, NC (United States)

    2016-10-15

    To investigate the detection rate of pulmonary nodules in ultralow-dose CT acquisitions. In this lung phantom study, 232 nodules (115 solid, 117 ground-glass) of different sizes were randomly distributed in a lung phantom in 60 different arrangements. Every arrangement was acquired once with standard radiation dose (100 kVp, 100 references mAs) and once with ultralow radiation dose (80 kVp, 6 mAs). Iterative reconstruction was used with optimized kernels: I30 for ultralow-dose, I70 for standard dose and I50 for CAD. Six radiologists examined the axial 1-mm stack for solid and ground-glass nodules. During a second and third step, three radiologists used maximum intensity projection (MIPs), finally checking with computer-assisted detection (CAD), while the others first used CAD, finally checking with the MIPs. The detection rate was 95.5 % with standard dose (DLP 126 mGy*cm) and 93.3 % with ultralow-dose (DLP: 9 mGy*cm). The additional use of either MIP reconstructions or CAD software could compensate for this difference. A combination of both MIP reconstructions and CAD software resulted in a maximum detection rate of 97.5 % with ultralow-dose. Lung cancer screening with ultralow-dose CT using the same radiation dose as a conventional chest X-ray is feasible. (orig.)

  14. Asbestos-related radiographic changes by ILO classification of 10 x 10 cm chest X-rays in a screening of the general population.

    Science.gov (United States)

    Hilt, B; Hillerdal, G; Lund-Larsen, P G; Lien, J T; Langård, S

    1995-02-01

    A sample of 1388 10 x 10 cm chest X-rays from a previous population screening of males aged 40+ years were reevaluated by use of the ILO classification. There were 1036 films of subjects from an industrialized town, and 352 from a rural community. The observed rates of parenchymal changes (profusion > or = 1/0) at the reevaluation were 1.3% in the urban community and 3.4% in the rural community. The corresponding figures for pleural changes were 5.0% and 0.6%, respectively. Based on additional questionnaire information on asbestos exposure, it was found that the radiographic changes were probably related to past asbestos exposure for 2.3% of the subjects from the urban community and 0.6% from the rural community. In cases of asbestos-related illnesses the mean time since first exposure to asbestos was 35.9 years, whereas the mean duration of the exposures was 11.4 years. The results seem to indicate that the ILO reassessment of the radiographs was more sensitive in detecting pleural changes than the previous clinical screening of both small and large films.

  15. Dose on the entrance surface of thyroid, crystalline lens and gonads during the chest X-rays studies; Dosis en la superficie de entrada de tiroides, cristalino y gonadas durante los examenes radiologicos de torax

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez G, R.; Guerra M, J. A.; Pinedo S, A.; Hernandez O, M.; Duran M, H. A.; Salas L, M. A.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98000 Zacatecas (Mexico); Rivera M, T. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, IPN, Av. Legaria No. 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Azorin N, J. [Universidad Autonoma Metropolita, Unidad Iztapalapa, Av. San Rafael Atlixco 186, 09340 Mexico D. F. (Mexico)], e-mail: rgg_df@hotmail.com

    2009-10-15

    There were a measurement series in General Hospital of Fresnillo in X-rays department in areas of X-1 and X-2 ray rooms and in a neonatal intensive care unit 2, the dose was determined on the entrance surface into eyes, thyroid and gonads for patients undergoing to X-rays study of tele chest by thermoluminescent dosimetry. 5 dosemeters were used in each of the scans, found the following dose ranges 20+{sub -} 23 {mu}Gy to 350 +{sub -} 41 {mu}Gy. With results we can conclude that the used procedures and the calibration equipment are adequate. (Author)

  16. Galaxy gas as obscurer - I. GRBs x-ray galaxies and find an NH3∝ M_{star} relation

    Science.gov (United States)

    Buchner, Johannes; Schulze, Steve; Bauer, Franz E.

    2017-02-01

    An important constraint for galaxy evolution models is how much gas resides in galaxies, in particular, at the peak of star formation z = 1-3. We attempt a novel approach by letting long-duration gamma ray bursts (LGRBs) x-ray their host galaxies and deliver column densities to us. This requires a good understanding of the obscurer and biases introduced by incomplete follow-up observations. We analyse the X-ray afterglow of all 844 Swift LGRBs to date for their column density NH. To derive the population properties, we propagate all uncertainties in a consistent Bayesian methodology. The NH distribution covers the 1020-23 cm-2 range and shows no evolutionary effect. Higher obscurations, e.g. Compton-thick columns, could have been detected but are not observed. The NH distribution is consistent with sources randomly populating a ellipsoidal gas cloud of major axis {N^{major}H }=10^{23}cm^{-2} with 0.22 dex intrinsic scatter between objects. The unbiased SHOALS survey of afterglows and hosts allows us to constrain the relation between Spitzer-derived stellar masses and X-ray derived column densities NH. We find a well-constrained power-law relation of NH = 1021.7 cm-2 × (M⋆/109.5 M⊙)1/3, with 0.5 dex intrinsic scatter between objects. The Milky Way and the Magellanic clouds also follow this relation. From the geometry of the obscurer, its stellar mass dependence and comparison with local galaxies, we conclude that LGRBs are primarily obscured by galaxy-scale gas. Ray tracing of simulated Illustris galaxies reveals a relation of the same normalization, but a steeper stellar-mass dependence and mild redshift evolution. Our new approach provides valuable insight into the gas residing in high-redshift galaxies.

  17. The Evidence of Hyperinflation on Chest X Ray and its Correlation with Air Flow Obstruction in COPD Patients

    Directory of Open Access Journals (Sweden)

    Hassan Ghobadi

    2013-10-01

    Full Text Available Introduction: According  to  the  latest  statistical  and  epidemiological  studies,  COPD  will  become  the  fourth  leading  cause  of  death  in  2030  worldwide.  Scientists  are  studying  on  methods  to  diagnose  COPD  in  the  patients  in  early  stages,  because  it  is  a  curable  and  preventable  disease  in  early  stages.  In  this  study,  evidences  of  hyperinflation  on  CXR  of  COPD  patients  were  compared  with  pulmonary  function  test  (PFT  finding.    Materials  and  Methods: This  cross-sectional  study  was  done  on  100  patients  who  were  referred  to  the  pulmonary  clinic  with  symptoms  of  chronic  cough  and  dyspnea.  After  taking  history and  performing  physical  examination,  demographic  information,  history  of  smoking  and  bakery  and  frequency  of  exacerbations  were  recorded.  Standard  spirometry  was  performed  and  the  severity  of  COPD  was  determined  by  GOLD  (Global  initiative  for  chronic Obstructive  Lung  Disease  staging.  Additionally,  they  underwent  CXR  examination  (PA  and  lateral.  Collected  data  were  analyzed  in  SPSS  ver.  18. Results: In  this  study,  there  were  79  male  and  21  female. .. . .  The  patients,  64%  of  whom  were  urban  and  36%  were  rural  dwellers.  There  was  significant  correlation  between  FEF50%predict  with  sterno-diafragmatic  angle  and  retro-sternal  lucency  (p=0.01,  r=-0.26  and  p=0.01,  r=-0.25  respectively.  Also  there  were  significant  correlations  between  the  FEV1/FVC  with  retro-sternal  lucency  (p=0.006,  r=-0.27  and  FEV1%predict  with  sterno-diaphragmatic  angle  (p=0.002,  r=-0.31. Conclusion: The  study  showed  some  evidences  of  lung  hyperinflation  on  CXR  which

  18. Chest X-Ray (Chest Radiography)

    Science.gov (United States)

    ... passes through the body, recording an image on photographic film or a special detector. Different parts of ... on large film sheets (much like a large photographic negative). Today, most images are digital files that ...

  19. X-ray findings of small bowel taeniasis: A clinical and experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hong Soo; Kang, Hee Woong; Bahk, Yong Whee [St Mary' s Hospital Catholic Medical College, Seoul (Korea, Republic of)

    1972-12-15

    Unlike ascariasis of the small bowel, taeniasis can be detected radiologically with much difficulty because of the basic difference between the morphological features of each helminth. However once the characteristics of tape worms are appreciated and kept in mind, radiological diagnosis is fairly accurately made. In the present study we have reported typical radiological features of the small bowel taeniasis as observed in 6 adults patients seen at the Department of Radiology of St. Mary's Hospital and Holy Family Hospital, Catholic Medical College. Tapering tape-like or ribbon -like radiolucent shadows in distal small bowel appear unique. Compression spot film study of the ileum is most important in revealing such findings. An animal experiment using the swine small intestine and parasitological specimen of evacuated worm of taenia saginata was designed to help understand radiological manifestation in vivo.

  20. X-ray selected BALQSOs

    CERN Document Server

    Page, M J; Ceballos, M; Corral, A; Ebrero, J; Esquej, P; Krumpe, M; Mateos, S; Rosen, S; Schwope, A; Streblyanska, A; Symeonidis, M; Tedds, J A; Watson, M G

    2016-01-01

    We study a sample of six X-ray selected broad absorption line (BAL) quasi-stellar objects (QSOs) from the XMM-Newton Wide Angle Survey. All six objects are classified as BALQSOs using the classic balnicity index, and together they form the largest sample of X-ray selected BALQSOs. We find evidence for absorption in the X-ray spectra of all six objects. An ionized absorption model applied to an X-ray spectral shape that would be typical for non-BAL QSOs (a power law with energy index alpha=0.98) provides acceptable fits to the X-ray spectra of all six objects. The optical to X-ray spectral indices, alpha_OX, of the X-ray selected BALQSOs, have a mean value of 1.69 +- 0.05, which is similar to that found for X-ray selected and optically selected non-BAL QSOs of similar ultraviolet luminosity. In contrast, optically-selected BALQSOs typically have much larger alpha_OX and so are characterised as being X-ray weak. The results imply that X-ray selection yields intrinsically X-ray bright BALQSOs, but their X-ray sp...

  1. Dose evaluation for paediatric chest x-ray examinations in Brazil and Sudan: low doses and reliable examinations can be achieved in developing countries

    Science.gov (United States)

    Mohamadain, K. E. M.; da Rosa, L. A. R.; Azevedo, A. C. P.; Guebel, M. R. N.; Boechat, M. C. B.; Habani, F.

    2004-03-01

    Radiation protection in paediatric radiology deserves special attention since it is assumed that children are more sensitive to radiation than adults. The aim of this work is to estimate the entrance skin dose (ESD), the body organ dose (BOD) and the effective dose (E) for chest x-ray exposure of paediatric patients in five large units, three in Sudan and two in Brazil, and to compare the results obtained in both countries with each other and with other values obtained by some European countries. Two examination projections have been investigated, namely, postero-anterior (PA) and antero-posterior (AP). The age intervals considered were: 0-1 year, 1-5 years, 5-10 years and 10-15 years. The results have been obtained with the use of a software called DoseCal. Results of mean ESD for the age interval 1-5 years and AP projection are: 66 µGy (Instituto de Pediatria e Puericultura Martagão Gesteira—IPPMG Hospital), 41, 86 and 68 µGy (Instituto Fernandes Figueira—IFF Hospital), 161 µGy (Omdurman Hospital), 395 µGy (Khartoum Hospital) and 23 µGy (Ahmed Gasim Hospital). In the case of the IFF Hospital, the results refer, respectively, to rooms 1, 2 and for the six mobile equipments. The reference dose values given by the European Guidelines were exceeded in the Khartoum Hospital whilst in all the other hospitals results obtained were below CEC reference values and comparable with the results found in Sweden, Germany, Spain and Italy. The mean E for the same age interval was 11 µSv in the IPPMG, 6, 15 and 11 µSv in the IFF, respectively for rooms 1, 2 and the 6 mobiles, 25 µSv in the Omdurman Hospital, 45 µSv in the Khartoum Hospital and 3 µSv in the Ahmed Gasim Hospital. These are some examples of the large discrepancies that have been detected in this survey.

  2. Dose evaluation for paediatric chest x-ray examinations in Brazil and Sudan: low doses and reliable examinations can be achieved in developing countries

    Energy Technology Data Exchange (ETDEWEB)

    Mohamadain, K E M [FIOCRUZ-Escola Nacional de Saude Publica-CESTEH, Rua Leopoldo Bulhoes 1480, Manguinhos, 21041-210 Rio de Janeiro (Brazil); Rosa, L A R da [Departamento de FIsica Medica, Instituto de Radioprotecao e Dosimetria, Comissao Nacional de Energia Nuclear, 22780-160 Rio de Janeiro (Brazil); Azevedo, A C P [FIOCRUZ-Escola Nacional de Saude Publica-CESTEH, Rua Leopoldo Bulhoes 1480, Manguinhos, 21041-210 Rio de Janeiro (Brazil); Guebel, M R N [Instituto de Pediatria e Puericultura Martagao Gesteira, UFRJ, 21490-910 Rio de Janeiro (Brazil); Boechat, M C B [FIOCRUZ-Instituto Fernandes Figueira, Rio de Janeiro (Brazil); Habani, F [Physics Department, Faculty of Sciences, Khartoum University, Khartoum (Sudan)

    2004-03-21

    Radiation protection in paediatric radiology deserves special attention since it is assumed that children are more sensitive to radiation than adults. The aim of this work is to estimate the entrance skin dose (ESD), the body organ dose (BOD) and the effective dose (E) for chest x-ray exposure of paediatric patients in five large units, three in Sudan and two in Brazil, and to compare the results obtained in both countries with each other and with other values obtained by some European countries. Two examination projections have been investigated, namely, postero-anterior (PA) and antero-posterior (AP). The age intervals considered were: 0-1 year, 1-5 years, 5-10 years and 10-15 years. The results have been obtained with the use of a software called DoseCal. Results of mean ESD for the age interval 1-5 years and AP projection are: 66 {mu}Gy (Instituto de Pediatria e Puericultura Martagao Gesteira-IPPMG Hospital), 41, 86 and 68 {mu}Gy (Instituto Fernandes Figueira-IFF Hospital), 161 {mu}Gy (Omdurman Hospital), 395 {mu}Gy (Khartoum Hospital) and 23 {mu}Gy (Ahmed Gasim Hospital). In the case of the IFF Hospital, the results refer, respectively, to rooms 1, 2 and for the six mobile equipments. The reference dose values given by the European Guidelines were exceeded in the Khartoum Hospital whilst in all the other hospitals results obtained were below CEC reference values and comparable with the results found in Sweden, Germany, Spain and Italy. The mean E for the same age interval was 11 {mu}Sv in the IPPMG, 6, 15 and 11 {mu}Sv in the IFF, respectively for rooms 1, 2 and the 6 mobiles, 25 {mu}Sv in the Omdurman Hospital, 45 {mu}Sv in the Khartoum Hospital and 3 {mu}Sv in the Ahmed Gasim Hospital. These are some examples of the large discrepancies that have been detected in this survey.

  3. Laryngotracheobronchial papillomatosis: findings on computed tomography scans of the chest

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. de Radiologia; Araujo Neto, Cesar de [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Dept. de Radiologia; Meirelles, Gustavo Souza Portes [Universidade Federal de Sao Paulo (UNIFESP-EPM), SP (Brazil); Irion, Klaus Loureiro [The Royal Liverpool University Hospital, Liverpool (United Kingdom); Zanetti, Glaucia [Faculdade de Medicina de Petropolis (FMP), RJ (Brazil); Missrie, Israel [Universidade Federal de Sao Paulo (UNIFESP-EPM), SP (Brazil). Dept. de Diagnostico por Imagem; Sato, Juliana [Universidade Federal de Sao Paulo (UNIFESP-EPM), SP (Brazil). Dept. de Otorrinolaringologia e Cirurgia de Cabeca e Pescoco

    2008-12-15

    Objectives: To present the findings of computed tomography (CT) scans of the chest in patients with laryngotracheobronchial papillomatosis. Methods: We retrospectively analyzed CT scans of eight patients, five males and three females, ranging from 5 to 18 years of age with a mean age of 10.5 years. Images were independently reviewed by two radiologists. In discrepant cases, a consensus was reached. Results: The most common CT findings were intratracheal polypoid lesions and pulmonary nodules, many of which were cavitated. Conclusions: In patients with laryngotracheobronchial papillomatosis, the most common tomographic finding was the combination of intratracheal polypoid lesions and multiple pulmonary nodules, many of which were cavitated. (author)

  4. Skull x-ray

    Science.gov (United States)

    X-ray - head; X-ray - skull; Skull radiography; Head x-ray ... There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most ...

  5. Neck x-ray

    Science.gov (United States)

    X-ray - neck; Cervical spine x-ray; Lateral neck x-ray ... There is low radiation exposure. X-rays are monitored so that the lowest amount of radiation is used to produce the image. Pregnant women and ...

  6. Regional cerebral blood flow measurement by N-isopropyl-p-(/sup 123/I) iodoamphetamine. A comparison with X-ray CT findings in hemiplegic patients

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, Y.; Kuriyama, M.; Sudo, M.; Maeda, N.; Ishii, Y.; Konishi, K.; Nakamura, K.

    1987-05-01

    Eight patients with hemiplegia in chronic stages were studied with N-isopropyl-p-(/sup 123/I) iodoamphetamine (IMP) and single-photon emission computed tomography (SPECT) comparing with X-ray CT findings. In three patients, focal decreases of IMP were observed and these areas were larger than the abnormal areas found by X-ray CT. In the other five patients, hemispherical low perfusion of IMP was observed by SPECT, but X-ray CT showed severe atrophy with normal density. In two patients, cerebral angiography showed no abnormalities in the arterial phase. Regional cerebral blood flow measurement using IMP would be of great value in evaluating abnormal cerebral functions in the chronic state of acute infantile hemiplegia and cerebral palsy.

  7. 急性心源性肺水肿临床疗效与X线胸片的相关性分析%Analysis the relationship between therapeutic effect of acute cardiogenic pulmonary edema and chest X-ray features

    Institute of Scientific and Technical Information of China (English)

    李晶晶; 董磊

    2013-01-01

    Objective To study the relationship between therapeutic effect of acute cardiogenic pulmonary edema (ACPE)and chest X-ray features.To offer an assessment method to clinical therapy. Methods Forty-eight patients with ACPE were recruited in the study. After treatment all the changes of chest X-ray features were analyzed by two salty radiologists using double blind method retrospectively.Statistics method were χ2 analysis and Kappa analysis. Results Two doctors found the patients with better therapeutic effect also have obviously changes of chest X-ray(P<0.05).The two doctors’film reading have the same concordance (P<0.05). Conclusion It’s important to recheck chest X-ray during the clinical therapy of patients with ACPE.%  目的研究急性心源性肺水肿治疗效果和X线胸片表现之间的关系,为临床评估疗效提供帮助。方法由2名有经验的放射科医师采用盲法回顾性分析48例急性心源性肺水肿患者治疗前后的X线胸片好转率,所得的数据做χ2检验,并用Kappa检验对2人评判的结果做一致性分析。结果医师甲、乙所得的结论均为:急性心源性肺水肿临床治疗后好转者,X线胸片好转率的差异有统计学意义(P<0.05)。甲乙医师间阅片的一致性分析差异有统计学意义(P<0.05),说明甲乙2名医师对治疗前后X线表现好转与否的诊断结果有较好的一致性。讨论急性心源性肺水肿治疗过程中复查X线胸片,是评估临床疗效的一种有效的方法。

  8. Mucopolysaccharidosis: abnormal findings on abdomen and chest excluding musculoskeletal system

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Jeung Hee; Yoon, Dae Young; Seo, Young Lan; Han, Dae Hee; Choi, Chul Soon; Bae, Sang Hoon; Yoon, Young Cheol; Park, Sang Joon [Samsung Medical Center, Seoul (Korea, Republic of); Kim Han, Bok Yung; Yoon, Hye Kyung; Cho, Jae Min [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2003-06-01

    Mucopolysaccharidosis (MPS) is a lysosomal storage disease that causes tissue distortion and dysfunction due to the infiltration of mucopolysaccharide in connective tissue. The purpose of this study was to evaluate the characteristic findings of abdominal CT and plain chest radiography in patients with MPS. Sixty-two children with MPS diagnosed by urine analysis were involved in this study; 24 of these underwent abdominal CT and the findings were reviewed by two radiologists, who reached a consensus. Organomegaly was classified as severe, moderate or mild. On chest PA radiographs of 42 of the children, the transverse diameter of the trachea was measured and compared with that of 42 normal controls. Student's t test was used for statistical analysis. At abdominal CT, hepatomegaly was observed in 22 patients (92%; 2 severe, 15 moderate and 5 mild); and splenomegaly was present in 18 (75%; 2 severe, 4 moderate and 12 mild). Among eight patients(33%) with pancreatic enlargement, one had a severly enlarged pancreas, while in the remaining seven, enlargement was mild. Also present were inguinal hernia (n=15), umbilical hernia (n=12), undulation with thickening of the diaphragmatic crura (n=10), abnormalities related to the male genitalia (n=5) and vascular anomaly (n=3). In MPS patients, the mid-point diameter of the trachea (range, 5.6-9 mm; mean, 6.9 mm) was significantly less than in normal controls (range, 8-14 mm; mean, 10.8 mm) (p<0.001). An awareness of the characteristic abnormalities observed at abdominal CT and chest PA radiography can lead to a better understanding of MPS in children.

  9. Mucopolysaccharidosis: abnormal findings on abdomen and chest excluding musculoskeletal system

    Energy Technology Data Exchange (ETDEWEB)

    KimHan, Bo Kyung; Yoon, Hye Kyung; Cho, Jae Min [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Moon, Jeung Hee; Yoon, Dae Young; Seo, Young Lan; Han, Dae Hee; Choi, Chul Soon; Bae, Sang Hoon; Yoon, Young Cheol; Park, Sang Joon [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2003-06-01

    Mucopolysaccharidosis (MPS) is a lysosomal storage disease that causes tissue distortion and dysfunction due to the infiltration of mucopolysaccharide in connective tissue. The purpose of this study was to evaluate the characteristic findings of abdominal CT and plain chest radiography in patients with MPS. Sixty-two children with MPS diagnosed by urine analysis were involved in this study; 24 of these underwent abdominal CT and the findings were reviewed by two radiologists, who reached a consensus. Organomegaly was classified as severe, moderate or mild. On chest PA radiographs of 42 of the children, the transverse diameter of the trachea was measured and compared with that of 42 normal controls. Student's t test was used for statistical analysis. At abdominal CT, hepatomegaly was observed in 22 patients (92%; 2 severe, 15 moderate and 5 mild); and splenomegaly was present in 18 (75%; 2 severe, 4 moderate and 12 mild). Among eight patients (33%) with pancreatic enlargement, one had a severly enlarged pancreas, while in the remaining seven, enlargement was mild. Also present were inguinal hernia (n=15), umbilical hernia (n=12), undulation with thickening of the diaphragmatic crura (n=10). abnormalities related to the male genitalia (n=5) and vascular anomaly (n=3). In MPS patients, the mid-point diameter of the trachea (range, 5.6-9 mm; mean, 6.9 mm) was significantly less than in normal controls (range, 8-14 mm; mean, 10.8 mm)(p<0.001). An awareness of the characteristic abnormalities observed at abdominal CT and chest PA radiography can lead to a better understanding of MPS in children.

  10. X-Rays

    Science.gov (United States)

    X-rays are a type of radiation called electromagnetic waves. X-ray imaging creates pictures of the inside of ... different amounts of radiation. Calcium in bones absorbs x-rays the most, so bones look white. Fat ...

  11. Medical X-Rays

    Science.gov (United States)

    ... Benefits The discovery of X-rays and the invention of CT represented major advances in medicine. X- ... in X-ray and CT Examinations — X-ray definition, dose measurement, safety precautions, risk, and consideration with ...

  12. 胸部X线、CT和纤维支气管镜对肺癌诊断的应用研究%Study of Diagnosis of Chest X ray, CT and Bronchoscopy in Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    董乐; 张锡海; 韩璐璐; 刘钊

    2015-01-01

    Objective To analyze and discuss the meaning and value of chest X-ray, CT and fibrobronchoscope. Methods Select-ed 140 cases of patients with lung cancer in our hospital from January 2013 to January 2015 as a study object, according to the different of imaging detection scheme divided into CT group, X-gray group and fibrobronchoscope group, and analysis of the effect of the three detection methods in the treatment of patients. Results The accuracy rate of X-ray was 171/235 (72.77%), accuracy of CT examination for 211/235 (89.79%), the accuracy rate of fiberoptic bronchoscopy for 221/235 (94.04%) was higher than that of X-ray, CT, there was significant difference(χ2=5.37, P<0.05); fiberoptic bronchoscopy was higher than that of X-ray, there were statistically significant differences (χ2=6.81,P<0.05);fiberoptic bronchoscopy the mirror is higher than that of CT, but the difference was not statistically significant(χ2=0.67, P<0.05).Over 60% lung cancer patients can be clinically diagnosed only by chest X-ray, the accurate rate of peripheral lung cancer can be diagnosed by CT while central lung cancer can be diagnosed by fibrobroncho-scope. Conclusion It was showed that Chest X-ray should be used firstly in the diagnosis of lung cancer, and CT or fibrobroncho-scope can greatly improve the diagnostic accuracy of lung cancer, which is worthy of promotion and application.%目的 分析和研究胸部X线、 螺旋 CT及纤维支气管镜在诊断中的价值和意义. 方法 随机抽取于 2013年1月-2015年1月间在该院就诊的140例肺癌患者作为研究对象,并根据检查方法的不同分为X线、CT、支气管镜,所有患者均进行以上检查,对比和分析各种方法在诊断中的准确性. 结果 X线检查的准确率为171/235(72.77%),CT检查的准确率为211/235(89.79%),纤维支气管镜的准确率为221/235(94.04%),CT高于X线,差异有统计学意义(χ2=5.37,P<0.05);纤维支气管镜高于X线,差异有统计学意义(χ2=6.81,P<0

  13. Diagnostic value of the conventional chest X-ray for the assessment of the haemodynamics after combined aortic mitral valve replacement

    Energy Technology Data Exchange (ETDEWEB)

    Krestin, G.P.; Neufang, K.F.R.; Carstens, V.

    1982-11-01

    Conventional roentgenograms of 25 patients who underwent combined aortic and mitral valve replacement were evaluated and correlated with pre- and postoperative functional and haemodynamic parameters. The roentgenograms were obtained 6 months before and up to 24 months after valve replacement. A reduction in heart size could be seen in nearly all patients. This was independent of clinical and haemodynamic results. An increase in heart size always suggests severe haemodynamic worsening, especially a paravalvular leakage. The most valuable X-ray sign is the degree of pulmonary congestion, which is well correlated with the cardiac index.

  14. Use of Fourier domain filtering and dynamic programming in finding a titanium coil implant in high voltage x-ray images

    DEFF Research Database (Denmark)

    Nielsen, Henning; Hansen, Jesper Carl

    2006-01-01

    This paper deals with the problem of finding precise position and orientation of a titanium coil implant in humans. Analysis of high voltage X-rays stereo images are used to determine the true 3D position. High voltage images inherently presents with poor contrast. Various image processing techni...... determined the position of the titanium wire within less than 1 mm of ground truth determined from manual analysis of the images....

  15. The Image Quality of a Digital Chest X-Ray Radiography System: Comparison of Quantitative Image Quality Analysis and Radiologists' Visual Scoring

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ji Ho [Dept. of Radiology Oncology, Yongsan Hospital, Pusan National University College of Medicine, Yongsan (Korea, Republic of); Chung, Myung Jin [Dept. of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Park, Darl; Kim, Won Taek; Kim, Yong Ho; Ki, Yong Kan; Kim, DFong Hyun; Lee, Ju Hee; Kim, Dong Won [Dept. of Radiology Oncology, Yongsan Hospital, Pusan National University College of Medicine, Yongsan (Korea, Republic of); Jeon, Ho Sang [Reserach Institue for Convergence of Biomedical Science and Technology, Yongsan Hospital, Pusan National University College of Medicine, Yongsan (Korea, Republic of)

    2011-11-15

    To evaluate the performance of imaging devices, which should be periodically monitored to maintain high quality images to the radiologists. Additionally, this evaluation may prevent patients from radiation over-exposure. The most suitable engineering standard for imaging performance evaluation of digital X-ray thoracic images was determined. IEC 62220-1 standards were used to evaluate the performance of the images. In succession, the visibilities of overall image, pneumothorax, and humerus head in anthropomorphic thoracic phantom images were used to evaluate the image qualities by radiologists. The rank correlation coefficient (p) of visual scoring by radiologists with system spatial resolution is not meaningful (p-value, p = 0.295), but is significant with image noise (p-value, p -0.9267). Finally, the noise equivalent quanta (NEQ) presents a high rank correlation for visual scoring of radiologists (p-value, p = 0.9320). Image quality evaluation of radiologists were mainly affected by imaging noise. Hence, the engineered standard for evaluating image noise is the most important index to effectively monitor the performance of X-ray images. Additionally, the NEQ can be used to evaluate the performance of radiographic systems, because it theoretically corresponds to the synthetic image quality of systems.

  16. Finding High Quality Young Star Candidates in Ceph C using X-ray, Optical, and IR data

    Science.gov (United States)

    Orr, Laura; Rebull, Luisa M.; Johnson, Milton; Miller, Alexandra; Aragon Orozco, Anthony; Bakhaj, Benjamin; Bakshian, Jacquelyn; Chiffelle, Elizabeth; DeLint, Arie; Gerber, Stefan; Mader, Jared; Marengo, Amelia; McAdams, Jesse; Montufar, Cassandra; Orr, Quinton; San Emeterio, Lis; Stern, Eliyah; Weisserman, Drew

    2017-01-01

    We looked for new candidate young stars within the star forming region of Ceph OB3, more specifically in a region of this molecular cloud called Ceph C. While this region lies in the galactic plane and is included in several large surveys, Ceph C has not been well studied in the past and few young stellar objects (YSOs) have been identified there. The YSOVAR team (Rebull et al. 2014) has time-series monitoring data of this region, and in order to understand the diversity of the light curves, it is crucial to understand which objects in the field of view are likely YSOs, and which are foreground/background objects. The goal of our study is to identify candidate YSO sources as well as support the greater understanding of the variety, evolution, and variability of young stars. Our search for young stars includes data in X-ray, optical, and IR. Data points used are from Chandra, SDSS, IPHAS, 2MASS, Spitzer IRAC and MIPS, and WISE, giving us data over many orders of magnitude, 0.001 to 25 microns (0.36 to 25 microns without the X-rays). The catalogs were merged across all available wavelengths. Each source was inspected in all available images to insure good matches and quality of data across wavelengths and to eliminate poor candidates, those with contamination or confusion, and non-YSO objects. Spectral energy distributions (SEDs) for each candidate YSO were constructed and compared to images for greater assessment and reliable YSO identification. Color-color and color-magnitude diagrams have been created for the sources in this region and are used in conjunction with images, SEDs, X-ray, IR excess, and variability properties to identify candidate YSOs. Support provided for this work by the NASA/IPAC Teacher Archive Research Program (NITARP), which receives funding from the NASA ADP program.

  17. Chest Traumatic Pulmonary Hemorrhage of X-Ray Plain Film, CT Diagnosis Analysis%胸部损伤性肺出血的X线平片、CT诊断分析

    Institute of Scientific and Technical Information of China (English)

    陆忠才

    2013-01-01

    Objective:To study the chest traumatic pulmonary hemorrhage of X-ray plain film, CT diagnosis application value. Methods:The diagnosis and treatment in our hospital of 66 cases of chest injury patients with pulmonary hemorrhage, the implement X-ray plain film and CT diagnosis, to the patient to diagnose. Results:Through to all patients in X-ray plain film and CT diagnosis, image display performance for pulmonary interstitial change have 23 cases, accounting for 34.8%, affects the performance show for lung parenchyma real variable shadow of 24 cases, accounting for 36.4%, display for traumatic pulmonary cyst of 11 cases, accounting for 16.7%, shown as the lungs hematoma of 8 cases, accounting for 12.1%. Conclusion:The chest traumatic pulmonary hemorrhage disease.%目的:探讨胸部损伤性肺出血的X线平片、CT诊断应用价值。方法:选取在我院诊治的66例胸部损伤性肺出血患者,对其实行X线平片及CT诊断,以对患者的病情进行确诊。结果:通过对所有患者实行X线平片及CT诊断,影像表现显示为肺间质性改变的有23例,占34.8%,影响表现显示为肺实质实变影的有24例,占36.4%,显示为创伤性肺囊肿的有11例,占16.7%,显示为肺内血肿的有8例,占12.1%。结论:胸部损伤性肺出血疾病。

  18. Galaxy gas as obscurer: I. GRBs x-ray galaxies and find a N_H ~ M* relation

    CERN Document Server

    Buchner, Johannes; Bauer, Franz E

    2016-01-01

    An important constraint for galaxy evolution models is how much gas resides in galaxies, in particular at the peak of star formation z=1-3. We attempt a novel approach by letting long-duration Gamma Ray Bursts (LGRBs) x-ray their host galaxies and deliver column densities to us. This requires a good understanding of the obscurer and biases introduced by incomplete follow-up observations. We analyse the X-ray afterglow of all 844 Swift LGRBs to date for their column density $N_H$. To derive the population properties we propagate all uncertainties in a consistent Bayesian methodology. The $N_H$ distribution covers the $10^{20-23}\\mathrm{cm}^{-2}$ range and shows no evolutionary effect. Higher obscurations, e.g. Compton-thick columns, could have been detected but are not observed. The $N_H$ distribution is consistent with sources randomly populating a ellipsoidal gas cloud of major axis $N_H^\\text{major}=10^{23}\\mathrm{cm}^{-2}$ with 0.22 dex intrinsic scatter between objects. The unbiased SHOALS survey of after...

  19. Effectiveness of Medical Chest X-ray Shielding by an Orthostatic Screen%医用X射线摄影立位防护屏的防护效果

    Institute of Scientific and Technical Information of China (English)

    李敏明; 徐敏; 李文婧

    2011-01-01

    [目的] 探讨医用X射线摄影立位防护屏的使用对受检者的防护效果.[方法] 利用放热释光剂量计检测立位防护屏前后和常用个人防护用品里外的辐射剂量,比较并分析这两类屏蔽防护的效果.[结果] 立位防护屏和个人防护用品对主射线的屏蔽效果基本相同,但使用立位防护屏,将增加一些散射辐射.[结论] 立位防护屏使用方便,受检者易接受,对主射线的屏蔽效果明显,但其带来的散射线对受检者的影响也应予以重视.%[ Objective ] To examine effectiveness of an orthostatic shielding screen in medical Chest X-ray photography.[ Methods ] The radiation doses on/under a shielding screen and a regular personal protective equipment( PPE )were measured by a thermoluminescent dosimeter. The protection effectiveness between the two shielding methods were compared. [ Results ] The protection effectiveness of primary X-rays were nearly the same by using the orthostatic screen and the PPEs. However, scattering radiation were detected in using the screen. [ Conclusion ] The orthostatic shielding screen is convenient and more compliant to examinees. It showed an obvious protection to primary X-rays, but the scattering radiation could be an issue in its application.

  20. 胸片和临床症状肺结核筛查的应用价值%Application Value of Chest X-Ray and Clinical Symptoms of Pulmonary Tuberculosis Screening

    Institute of Scientific and Technical Information of China (English)

    张延安

    2014-01-01

    Objective: To evaluate the value of clinical application of chest X-ray and clinical symptoms of pulmonary TB screening. Methods:All objects by symptoms, chest X-ray screening questionnaire (CXR), and (or) sputum smear or culture. Results:There were abnormal CXR sensitivity was 94%, specificity was 73%. The sensitivity of screening with symptoms was 90%, the specificity was 32%. Smear microscopy failed to increase the suspicious patients, joint symptoms and CXR screening sensitivity was 100%, specificity was 65%. Conclusion:Only by CXR screening showed that the accuracy of screening compared with symptoms of high, combined with CXR and symptom screening has the highest sensitivity.%目的:评估胸片和临床症状对肺TB筛查的应用价值。方法:所有对象经症状问卷筛查、胸片(CXR)、和(或)痰涂片或培养。结果:存在CXR异常者敏感性为94%,特异性为73%。症状筛查结合的敏感性为90%,特异性为32%。涂片显微镜检查未能增加可疑病人,联合症状和CXR筛查敏感性达100%,特异性达65%。结论:仅用CXR筛查即呈现较单纯症状筛查高的准确度,联合CXR和症状筛查有最高的敏感性。

  1. 重症手足口病患儿并发肺水肿的胸部X线表现分析%Chest X-ray Manifestation Analysis of Severe Hand Foot Mouth Ddisease with Pulmonary Edeman in Children

    Institute of Scientific and Technical Information of China (English)

    程军林; 刘凯; 汪欢; 徐子魁

    2012-01-01

    目的 探讨重症手足口病(hand-foot-mouth disease,HFMD)患儿并发肺水肿的胸部X线表现.资料与方法 对14例临床确诊为重症HFMD并发肺水肿患儿的胸部X线平片进行回顾性分析.结果 重症HFMD患儿并发肺水肿的胸部X线表现为双肺广泛分布的实变影,病变密度多样,可分布于肺野的内、中、外带,肺尖和/或肋膈角区域较少累及或累及程度较轻;随着病情的变化,肺水肿易反复,表现为加重与消散交替变化.结论 重症HFMD患儿并发肺水肿的胸部X线表现能够反映病情变化,对指导临床治疗及判断预后具有重要参考价值.%Objective To investigate the X-ray manifestation of severe hand foot mouth disease with pulmonary edeman in children. Materials and Methods Clinical data of 14 patients were analyzed retrospectively. Results The chest X-ray of severe hand foot mouth disease showed that there were diffuse infiltrative shadows or even patchy consolidations over both lung fields. The density of the lesion was diversify ,it could be dispersed inside ,in central or outside the lung fields, apex and costo phrenic angle was invaded rarely. As the disease progress,the edema would aggravate or disappear,and the density and the ambit of the manifest changed. Conclusion The chest X-ray manifestation of severe hand foot mouth disease with pulmonary edema in children can reflect the patient' s condition. It is very worth to guide the clinic treatment and the prognosis.

  2. Abdominal x-ray

    Science.gov (United States)

    ... are, or may be, pregnant. Alternative Names Abdominal film; X-ray - abdomen; Flat plate; KUB x-ray ... Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also ...

  3. Extremity x-ray

    Science.gov (United States)

    ... degenerative) Bone tumor Broken bone (fracture) Dislocated bone Osteomyelitis (infection) Arthritis Other conditions for which the test ... Bone tumor Bone x-ray Broken bone Clubfoot Osteomyelitis X-ray Review Date 7/3/2016 Updated ...

  4. On Pneumonic Chest X-rays of Chronic Psychoses%慢性精神病住院患者肺炎X线影像

    Institute of Scientific and Technical Information of China (English)

    李云

    2012-01-01

    目的:分析慢性精神病住院患者肺炎的X线影像。方法:对120例慢性精神病住院患者肺炎的X线影像进行分析,总结其特点。结果:120例肺炎患者中,大叶性肺炎30例,小叶性、间质性肺炎90例;大叶性肺炎以中青年人为主,病程2年以下多见,病灶以右肺中上肺野、左肺下野片状阴影为主;小叶性、间质性肺炎以老年多见,病程4年以上,病灶以两肺下野斑点状、索条状阴影为主。结论:慢性精神病住院患者病情特殊,临床症状不明显,需密切观察病情,早检查、早诊断、早治疗。%Objective: To analyze chest rays of chronic psychoses affected pneumonia. Methods: Based on the analysis of chest Xrays of patients in hospital, the characteristics of pneumonia are summarized. Results: Among 120 cases, there are 30 lobar cases, 90 lobular and interstitial cases. Lobar pneumonia is the most common inflection occurring in middle and young people, their disease course usually lasts for less than 2 years. The focus of their disease lies in the middle upper fight lung field, the lower left lung field is mainly in shadow. While lobular and interstitial pneumonia is the most common inflection occurring in the aged people, their disease course usually lasts for less than 4 years. The focus of their disease lies in the lower field of two lungs, mottled and striped in shadow. Conclusion:The condition of such patients is special. The clinical manifestation is invisible. So related measures should be taken, it's better to observe, test, diagnose and cure at its early stage.

  5. 慢性精神病患者感染肺结核的胸部X线分析%Analysis of Chest X-rays on Chronic Psychoses Infected by Pulmonary Tuberculosis

    Institute of Scientific and Technical Information of China (English)

    李云; 施慧仙

    2012-01-01

    Objective: To study the diagnosis value of chest X-rays on chronic psychoses who were infected by pulmonary tuberculosis.Methods: 78 infected cases that accorded with ICD-10 diagnosis standard were analyzed and the changes of their videognosis were observed.Results: The symptoms of pulmonary tuberculosis were continued and the pictures were varied.Conclusion: Those chronic psychoses confined to the hospital are susceptible to tuberculosis.The clinical manifestation is not so typical and easy to cure,and it is usually invisible and recurred.Regular tests of X-rays are the key means to discover the disease at its early stage.%目的:探讨胸部X线检查对慢性精神病患者感染肺结核的诊断价值。方法:对2007年至2010年慢性精神病住院患者胸部X线检查中发现符合ICD-10诊断标准的78例肺结核患者的胸部X线影像学特征进行分析。结果:78例肺结核感染者占同期慢性精神病住院患者的4.0%,结核病灶多位于上中肺野,以继发性肺结核最多,占73.1%(57/78),病变的影像表现多样,以多形态混合存在为主。结论:慢性精神病住院患者是肺结核的易感群体,应定期行胸部X线检查,对肺结核感染者进行必要的隔离和相应的治疗。

  6. Radiografia torácica e bacteriologia na fase inicial de tratamento de 800 pacientes masculinos com tuberculose pulmonar Chest X-ray and bacteriology in the initial phase of treatment of 800 male patients with pulmonary tuberculosis

    Directory of Open Access Journals (Sweden)

    Sefa Levent Ozsahin

    2011-06-01

    Full Text Available OBJETIVO: Avaliar radiografias de tórax de pacientes com tuberculose pulmonar e determinar se a extensão das lesões radiográficas correlaciona-se com os parâmetros bacteriológicos. MÉTODOS: Neste estudo descritivo e retrospectivo; foram avaliadas radiografias de tórax, baciloscopias para BAAR e culturas de escarro para Mycobacterium tuberculosis no momento basal e durante os dois primeiros meses de tratamento. A amostra foi composta por 800 pacientes masculinos internados entre 1995 até o presente em um hospital com 250 leitos no noroeste da Turquia. RESULTADOS: A VHS média inicial foi de 58 ± 37 mm/h. Inicialmente, a baciloscopia e as culturas de escarro tiveram resultado positivo em 83,8% e em 89,5% dos pacientes, respectivamente. Após o primeiro mês do tratamento, a proporção de culturas positivas foi maior nos pacientes com doença cavitária do que naqueles sem doença cavitária (53,7% vs. 37,7%; p 0.05 para todos, mas houve correlação positiva com VHS (r = 0,23, p OBJECTIVE: To evaluate chest X-rays of patients with pulmonary tuberculosis and to determine whether the extent of radiographic lesions correlates with bacteriological parameters. METHODS: In this retrospective, descriptive study, we evaluated chest X-rays, as well as AFB detection by smear microscopy and culture for Mycobacterium tuberculosis, initially and during the first two months of treatment, in 800 male patients hospitalized between 1995 and the present at a 250-bed hospital in northwestern Turkey. RESULTS: The initial mean ESR was 58 ± 37 mm/h. Initial sputum smears and cultures were positive in 83.8% and 89.5% of the patients, respectively. After the first month of treatment, the proportion of patients with positive sputum culture was higher among those with cavitary tuberculosis than among those with non-cavitary tuberculosis (53.7% vs. 37.7%, p 0.05 for all but was positively correlated with the ESR (r = 0.23, p < 0.001. During the first and second

  7. Chronic cough and a normal chest X-ray - a simple systematic approach to exclude common causes before referral to secondary care: a retrospective cohort study.

    Science.gov (United States)

    Turner, Richard D; Bothamley, Graham H

    2016-03-03

    Chronic cough is common in the community and can cause significant morbidity. It is not clear how closely treatment guidelines are used in general practice, or how often specialist referral is indicated. We aimed to assess the management of chronic cough in primary care before referral to a cough clinic, and to assess the outcome of managing chronic cough with an approach of simple investigation and empirical treatment trials. Data were extracted from the records of all patients attending a district general hospital respiratory clinic over a two-year period with isolated chronic cough lasting ⩾8 weeks. The clinic assessed symptoms with a cough-severity visual analogue scale and the Leicester Cough Questionnaire. Among 266 patients, the most frequent diagnoses were asthma (29%), gastro-oesophageal reflux (22%) and angiotensin-converting enzyme inhibitor use (14%). In all, 12% had unexplained chronic cough. Common diagnoses had often not been excluded in primary care: only 21% had undergone spirometry, 86% had undergone chest radiography and attempts to exclude asthma with corticosteroids had been made only in 39%. In the clinic few investigations were conducted that were not available in primary care. Substantial improvements in symptoms occurred with a median (interquartile range) total of 2 (2-3) clinic visits. We estimated that 87% of patients could have been managed solely in primary care; we did not identify distinguishing characteristics among this group. Most cases of chronic cough referred to secondary care could be managed with a simple and systematic approach, which is potentially transferrable to a community setting.

  8. X-Ray Supernovae

    CERN Document Server

    Immler, S; Immler, Stefan; Lewin, Walter H.G.

    2002-01-01

    We present a review of X-ray observations of supernovae (SNe). By observing the (~0.1--100 keV) X-ray emission from young SNe, physical key parameters such as the circumstellar matter (CSM) density, mass-loss rate of the progenitor and temperature of the outgoing and reverse shock can be derived as a function of time. Despite intensive search over the last ~25 years, only 15 SNe have been detected in X-rays. We review the individual X-ray observations of these SNe and discuss their implications as to our understanding of the physical processes giving rise to the X-ray emission.

  9. The sensitivity and specificity of using a computer aided diagnosis program for automatically scoring chest X-rays of presumptive TB patients compared with Xpert MTB/RIF in Lusaka Zambia.

    Directory of Open Access Journals (Sweden)

    Monde Muyoyeta

    Full Text Available OBJECTIVE: To determine the sensitivity and specificity of a Computer Aided Diagnosis (CAD program for scoring chest x-rays (CXRs of presumptive tuberculosis (TB patients compared to Xpert MTB/RIF (Xpert. METHOD: Consecutive presumptive TB patients with a cough of any duration were offered digital CXR, and opt out HIV testing. CXRs were electronically scored as normal (CAD score ≤ 60 or abnormal (CAD score > 60 using a CAD program. All patients regardless of CAD score were requested to submit a spot sputum sample for testing with Xpert and a spot and morning sample for testing with LED Fluorescence Microscopy-(FM. RESULTS: Of 350 patients with evaluable data, 291 (83.1% had an abnormal CXR score by CAD. The sensitivity, specificity, positive predictive value (PPV and negative predictive value (NPV of CXR compared to Xpert were 100% (95%CI 96.2-100, 23.2% (95%CI 18.2-28.9, 33.0% (95%CI 27.6-38.7 and 100% (95% 93.9-100, respectively. The area under the receiver operator curve (AUC for CAD was 0.71 (95%CI 0.66-0.77. CXR abnormality correlated with smear grade (r = 0.30, p<0.0001 and with Xpert CT(r = 0.37, p<0.0001. CONCLUSIONS: To our knowledge this is the first time that a CAD program for TB has been successfully tested in a real world setting. The study shows that the CAD program had high sensitivity but low specificity and PPV. The use of CAD with digital CXR has the potential to increase the use and availability of chest radiography in screening for TB where trained human resources are scarce.

  10. Actinomycosis of the Chest X-ray Plain Film and CT Imaging Features%胸部放线菌病的X线平片和CT影像特点研究

    Institute of Scientific and Technical Information of China (English)

    岳莉; 闫国梁

    2015-01-01

    Objective Analysis actinomycosis of the chest X-ray plain film and CT tomography imaging characteristics, the evaluation of the value of X-ray and CT in the diagnosis of the disease.Methods Choose from January 2005 to February 2015, in our hospital during the period, confirmed by laboratory tests for patients with thoracic actinomycosis 10 cases as the research object, all patients were performed X-ray plain film and CT tomography; CT images with a standard algorithm, multi plane restructuring image, image characteristics.Results This group of 10 cases with X-ray is, lateral chest plain film are displayed as mass and large dense shadow, but did not show empty, liquefied gas and lesions; CT examination results showed that 52 actinomycetes lesions involving 18 normal; 8 cases of patients with CT images show that mass as the main lesions, lung see more spots or patch around the lesions and the funicular fuzzy shadow; Mass in the thin wall, and hollow, thin wall smooth, hollow with low density liquefaction and scattered suspended gas oven shadow; CT scan showed to see gas-liquid surface; CT images of 10 cases were showed lesion adjacent pleural thickening, 8 cases of patients with lung CT images showed the door increases and/or mediastinal lymph nodes, 2 cases of right lung CT images showed patchy shadow merge mediastinal abscess.Conclusion X-ray plain film to check the chest actinomycosis cannot view demonstrates the focal area of cavity, liquid and gas, limited diagnostic value and CT tomography can display the details of the lesion, has the characteristic, has high diagnostic value.%目的:分析胸部放线菌病的X线平片和CT体层摄影术影像特点,评价X线及CT在诊断该病中的价值。方法选择2005年1月至2015年2月期间我院收治,经实验室检查证实为胸部放线菌病的患者10例为研究对象,所有患者均行X线平片和CT体层摄影术检查;CT影像采用标准算法、多平面重组图像,观

  11. Radiograma de tórax e tomografia computadorizada na avaliação do enfisema pulmonar Chest X-ray and computed tomography in the evaluation of pulmonary emphysema

    Directory of Open Access Journals (Sweden)

    Klaus Loureiro Irion

    2007-12-01

    Full Text Available O enfisema é uma condição do pulmão, caracterizada pelo aumento acima do normal no tamanho dos espaços aéreos distais ao bronquíolo terminal. Atualmente, o enfisema é a quarta causa de morte nos EUA, afetando 14 milhões de pessoas. O presente artigo descreve as principais ferramentas no diagnóstico por imagem do enfisema, desde o início até os dias de hoje. Relata as técnicas tradicionais, como radiograma de tórax, e as evoluções no campo da tomografia computadorizada (TC, como a TC de alta resolução e a densitovolumetria pulmonar por TC tridimensional.Emphysema is a condition of the lung, characterized by the abnormal increase in the size of the airspace distal to the terminal bronchioles. Currently, emphysema is the fourth leading cause of death in the USA, affecting 14 million people. The present article describes the principal tools in the imaging diagnosis of emphysema, from the early days until the present. We describe traditional techniques, such as chest X-ray, together with the evolution of computed tomography (CT to more advanced forms, such as high resolution CT, as well as three-dimensional CT densitometry and volumetric assessment.

  12. X-Ray Polarimetry

    CERN Document Server

    Kaaret, Philip

    2014-01-01

    We review the basic principles of X-ray polarimetry and current detector technologies based on the photoelectric effect, Bragg reflection, and Compton scattering. Recent technological advances in high-spatial-resolution gas-filled X-ray detectors have enabled efficient polarimeters exploiting the photoelectric effect that hold great scientific promise for X-ray polarimetry in the 2-10 keV band. Advances in the fabrication of multilayer optics have made feasible the construction of broad-band soft X-ray polarimeters based on Bragg reflection. Developments in scintillator and solid-state hard X-ray detectors facilitate construction of both modular, large area Compton scattering polarimeters and compact devices suitable for use with focusing X-ray telescopes.

  13. 胸部透视、胸部平片和MSCT对小儿气管、支气管异物的诊断价值分析%The Analysis of Diagnostic Value of Fluoroscopy of Chest, the Chest X-ray and Multislice Computed Tomography (MSCT) to the Foreign Bodies in the Trachea and Bronchi of the Children

    Institute of Scientific and Technical Information of China (English)

    魏相磊; 武玉丽

    2014-01-01

    Objective To explore the diagnostic value of fluoroscopy of chest, the chest X-ray and multislice computed tomography (MSCT) to the foreign bodies in the trachea and bronchi of the children, and compare the results and diagnosis accuracy to the foreign bodies in the trachea and bronchi. Methods 18 cases of suspected bronchial foreign body all given lfuoroscopy of chest, the chest X-ray and MSCT, even through axis scan images mutiplane restructuring (MPR), curved planar reformation (CPR), minimum density projection method (MinP) and CT virtual endoscopy (CTVE) etc. Image post-processing technology, and compare the images results with what be found by video bronchoscope examination. Results All cases are found foreign bodies by video bronchoscope examination. 1 case directly observed positive foreign body and 10 cases observed typical signs of indirect negative foreign body by lfuoroscopy of chest. 1 case directly observed positive foreign body and 9 cases observed typical signs of indirect negative foreign body by chest X-ray examination .meanwhile 17 cases directly observed positive foreign body by MSCT scan. Conclusion MSCT and image post-processing technology has important value in diagnosing trachea bronchial foreign body in children.%目的:探讨胸部X线透视、胸部平片和MSCT对气管支气管异物的诊断价值,比较三种方法对诊断支气管异物的正确率。方法对18例怀疑支气管异物的病例全部行胸透、胸部平片和MSCT检查,通过图像后处理工作站将MSCT轴位扫描图像进行多平面重组(MPR)、曲面重组(CPR)、最小密度投影法(MinP)和CT仿真内镜(CTVE)等图像重组,检查结果分别与支气管镜对照。结果18例经纤维支气管镜检查均发现异物。胸透直接观察到阳性异物1例,具有典型间接征象的阴性异物10例;胸部平片直接观察到阳性异物1例,具有典型间接征象的阴性异物9例;MSCT诊断支气管异物17

  14. Dental x-rays

    Science.gov (United States)

    ... X-rays are a form of high energy electromagnetic radiation. The x-rays penetrate the body to form ... for detecting cavities, unless the decay is very advanced and deep. Many ... The amount of radiation given off during the procedure is less than ...

  15. X-Ray Surveys

    CERN Document Server

    Giommi, P; Perri, M

    1998-01-01

    A review of recent developments in the field of X-ray surveys, especially in the hard (2-10 and 5-10 keV) bands, is given. A new detailed comparison between the measurements in the hard band and extrapolations from ROSAT counts, that takes into proper account the observed distribution of spectral slopes, is presented. Direct comparisons between deep ROSAT and BeppoSAX images show that most hard X-ray sources are also detected at soft X-ray energies. This may indicate that heavily cutoff sources, that should not be detectable in the ROSAT band but are expected in large numbers from unified AGN schemes, are in fact detected because of the emerging of either non-nuclear components, or of reflected, or partially transmitted nuclear X-rays. These soft components may complicate the estimation of the soft X-ray luminosity function and cosmological evolution of AGN.

  16. Pulmonary asymmetry on chest X-ray

    OpenAIRE

    Oliveira, R.; Martins, JD; H. Marques; Santos, O.; I. Freitas; Pinto, FF

    2010-01-01

    A ausência unilateral de uma artéria pulmonar é uma anomalia congénita rara. Os autores descrevem o caso de um rapaz de dois anos, sem antecedentes patológicos prévios e que é referenciado para avaliação após a detecção na telerradiografia de tórax de assimetria dos campos pulmonares com desvio do mediastino para a direita. A tomografia axial computorizada e a cintigrafia de perfusão pulmonar entretanto efectuadas, indicavam para a ausência da artéria pulmonar...

  17. The Influence of Magnetic Resonance Imaging Findings of Degenerative Disease on Dual-Energy X-ray Absorptiometry Measurements in Middle-Aged Men

    Energy Technology Data Exchange (ETDEWEB)

    Donescu, O.S.; Battie, M.C.; Videman, T. [Faculty of Rehabilitation Medicine and Dept. of Physical Therapy, Univ. of Alberta (Canada)

    2007-02-15

    Purpose: To examine degenerative features based on magnetic resonance imaging (MRI) measurements at the lumbar spine in relation to dual-energy X-ray absorptiometry (DXA), and to investigate whether bone mineral density (BMD) is reflected in the substitution of bone trabecular structure by fat at the vertebral body level indicated by MRI T1 relaxation time, endplate concavity, and hypertrophic (osteophytes and endplate sclerosis) MRI findings. Material and Methods: The sample for this cross-sectional study was composed of 102 subjects, 35-70 years old, from a population-based cohort. Data collection included DXA in the anterior-posterior projection at the L1-L4 vertebrae and right femoral neck, and MRI of the lumbar spine in the midsagittal plane. Results: Age, vertebral signal intensity, osteophytes, and endplate concavity collectively explained 20% of the variance in spine BMD. Conclusion: The study findings suggest that degenerative findings based on MRI measurements at the lumbar spine have an influence on bone assessment using DXA. Therefore, an overall bone assessment such as DXA might not offer an accurate measure of BMD.

  18. Clinical Findings in Patients with Splenic Injuries: Are Injuries to the Left Lower Chest Important?

    Directory of Open Access Journals (Sweden)

    Schneir, Aaron

    2001-07-01

    Full Text Available The purpose of this study was to describe the clinical findings in patients with splenic injury and to determine if isolated left lower chest injury may be the single clinical indicator of splenic injury. The medical records of all adult blunt trauma patients with splenic injury over a 14 month period were reviewed. Significant left lower chest injury was considered present if the patient had left sided pleuritic chest pain with tenderness to ribs 7-12 or if these ribs were visualized as fractured on any imaging study. Patients were considered to have clinical findings suggestive of splenic injury if they had pre-hospital or emergency department hypotension, abdominal pain or tenderness, a Glasgow coma scale < 15, or gross hematuria. Ninety patients had splenic injury. Thirty-nine (43%. 95% CI 33, 54% patients had significant left lower chest injury. In five (6%. 95% CI 2, 12% patients, injury to this portion of the chest was the single indicator of splenic injury. Nearly half the patients with splenic injury will have significant injury to the left lower chest and this finding may be the only indicator of splenic injury.

  19. X-ray crystallography

    Science.gov (United States)

    2001-01-01

    X-rays diffracted from a well-ordered protein crystal create sharp patterns of scattered light on film. A computer can use these patterns to generate a model of a protein molecule. To analyze the selected crystal, an X-ray crystallographer shines X-rays through the crystal. Unlike a single dental X-ray, which produces a shadow image of a tooth, these X-rays have to be taken many times from different angles to produce a pattern from the scattered light, a map of the intensity of the X-rays after they diffract through the crystal. The X-rays bounce off the electron clouds that form the outer structure of each atom. A flawed crystal will yield a blurry pattern; a well-ordered protein crystal yields a series of sharp diffraction patterns. From these patterns, researchers build an electron density map. With powerful computers and a lot of calculations, scientists can use the electron density patterns to determine the structure of the protein and make a computer-generated model of the structure. The models let researchers improve their understanding of how the protein functions. They also allow scientists to look for receptor sites and active areas that control a protein's function and role in the progress of diseases. From there, pharmaceutical researchers can design molecules that fit the active site, much like a key and lock, so that the protein is locked without affecting the rest of the body. This is called structure-based drug design.

  20. X-ray lasers

    CERN Document Server

    Elton, Raymond C

    2012-01-01

    The first in its field, this book is both an introduction to x-ray lasers and a how-to guide for specialists. It provides new entrants and others interested in the field with a comprehensive overview and describes useful examples of analysis and experiments as background and guidance for researchers undertaking new laser designs. In one succinct volume, X-Ray Lasers collects the knowledge and experience gained in two decades of x-ray laser development and conveys the exciting challenges and possibilities still to come._Add on for longer version of blurb_M>The reader is first introduced

  1. Dose levels in conventional X-rays; Niveles de dosis en radiografia convencional

    Energy Technology Data Exchange (ETDEWEB)

    Guerra M, J. A.; Gonzalez G, J. A.; Pinedo S, A.; Salas L, M. A.; Vega C, H. R. [Unidad Academica de Estudios Nucleares, Universidad Autonoma de Zacatecas, Cipres 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Rivera M, T. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, IPN, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Azorin N, J. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico)], e-mail: rgg_df@hotmail.com

    2009-10-15

    There were a series of measures in the General Hospital of Fresnillo in the X-ray Department in the areas of X-1 and X-2-ray rooms and in the neonatal intensive care unit 2, was determined the dose surface entry in eyes, thyroid and gonads for patients undergoing to X-ray study of chest Tele by thermoluminescent dosimetry. Five dosemeters were used in each one of the scans; so find the following dose ranges 20 +{sub -} 23 mGy to 350 +{sub -} 41 mGy. With the results obtained we can conclude that the procedures used and the equipment calibration is adequate. (Author)

  2. X-Ray Diffraction.

    Science.gov (United States)

    Smith, D. K.; Smith, K. L.

    1980-01-01

    Reviews applications in research and analytical characterization of compounds and materials in the field of X-ray diffraction, emphasizing new developments in applications and instrumentation in both single crystal and powder diffraction. Cites 414 references. (CS)

  3. Pelvis x-ray

    Science.gov (United States)

    X-ray - pelvis ... Tumors Degenerative conditions of bones in the hips, pelvis, and upper legs ... hip joint Tumors of the bones of the pelvis Sacroiliitis (inflammation of the area where the sacrum ...

  4. X-ray - skeleton

    Science.gov (United States)

    ... x-ray particles pass through the body. A computer or special film records the images. Structures that ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  5. Bone x-ray

    Science.gov (United States)

    ... or broken bone Bone tumors Degenerative bone conditions Osteomyelitis (inflammation of the bone caused by an infection) ... Multiple myeloma Osgood-Schlatter disease Osteogenesis imperfecta Osteomalacia Osteomyelitis Paget disease of the bone Rickets X-ray ...

  6. Hand x-ray

    Science.gov (United States)

    ... include fractures, bone tumors , degenerative bone conditions, and osteomyelitis (inflammation of the bone caused by an infection). ... chap 46. Read More Bone tumor Broken bone Osteomyelitis X-ray Review Date 9/8/2014 Updated ...

  7. Symbiotic Stars in X-rays

    Science.gov (United States)

    Luna, G. J. M.; Sokoloski, J. L.; Mukai, K.; Nelson, T.

    2014-01-01

    Until recently, symbiotic binary systems in which a white dwarf accretes from a red giant were thought to be mainly a soft X-ray population. Here we describe the detection with the X-ray Telescope (XRT) on the Swift satellite of 9 white dwarf symbiotics that were not previously known to be X-ray sources and one that was previously detected as a supersoft X-ray source. The 9 new X-ray detections were the result of a survey of 41 symbiotic stars, and they increase the number of symbiotic stars known to be X-ray sources by approximately 30%. Swift/XRT detected all of the new X-ray sources at energies greater than 2 keV. Their X-ray spectra are consistent with thermal emission and fall naturally into three distinct groups. The first group contains those sources with a single, highly absorbed hard component, which we identify as probably coming from an accretion-disk boundary layer. The second group is composed of those sources with a single, soft X-ray spectral component, which likely arises in a region where low-velocity shocks produce X-ray emission, i.e. a colliding-wind region. The third group consists of those sources with both hard and soft X-ray spectral components. We also find that unlike in the optical, where rapid, stochastic brightness variations from the accretion disk typically are not seen, detectable UV flickering is a common property of symbiotic stars. Supporting our physical interpretation of the two X-ray spectral components, simultaneous Swift UV photometry shows that symbiotic stars with harder X-ray emission tend to have stronger UV flickering, which is usually associated with accretion through a disk. To place these new observations in the context of previous work on X-ray emission from symbiotic stars, we modified and extended the alpha/beta/gamma classification scheme for symbiotic-star X-ray spectra that was introduced by Muerset et al. based upon observations with the ROSAT satellite, to include a new sigma classification for sources with

  8. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... that might interfere with the x-ray images. Women should always inform their physician and x-ray ... Safety page for more information about radiation dose. Women should always inform their physician or x-ray ...

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... drawer under the table holds the x-ray film or image recording plate . Sometimes the x-ray ... extended over the patient while an x-ray film holder or image recording plate is placed beneath ...

  10. Body composition study by dual-energy x-ray absorptiometry in familial partial lipodystrophy: finding new tools for an objective evaluation

    Directory of Open Access Journals (Sweden)

    Valerio Cynthia M

    2012-08-01

    Full Text Available Abstract Background Familial partial lipodystrophies (FPLD are clinically heterogeneous disorders characterized by selective loss of adipose tissue, insulin resistance and metabolic complications. Until genetic studies become available for clinical practice, clinical suspicion and pattern of fat loss are the only parameters leading clinicians to consider the diagnosis. The objective of this study was to compare body composition by dual energy X-ray absorptiometry (DXA in patients with FPLD and control subjects, aiming to find objective variables for evaluation of FPLD. Methods Eighteen female patients with partial lipodystrophy phenotype and 16 healthy controls, matched for body mass index, sex and age were studied. All participants had body fat distribution evaluated by DXA measures. Fasting blood samples were obtained for evaluation of plasma leptin, lipid profile and inflammatory markers. Genetic studies were carried out on the 18 patients selected that were included for statistical analysis. Thirteen women confirmed diagnosis of Dunnigan-type FPLD (FPLD2. Results DXA revealed a marked decrease in truncal fat and 3 folds decrease in limbs fat percentage in FPLD2 patients (p Conclusion In this study, assessment of body fat distribution by DXA permitted an objective characterization of FLPD2. A consistent pattern with marked fat reduction of lower body was observed in affected patients. To our knowledge this is the first time that cut-off values of objective variables were proposed for evaluation of FPLD2.

  11. X线胸片异常与粉尘暴露、吸烟、工龄等因素的相关性研究%Correlation study between dust exposures, smoking length of service and other factors and chest X-ray abnormalities

    Institute of Scientific and Technical Information of China (English)

    杨慧; 游志容; 梁海荣; 翟璐; 邵军丽; 唐焕文

    2013-01-01

    目的 了解石材加工工人粉尘暴露、吸烟、工龄等因素对X线胸片异常的影响,为预防该行业相关疾病的发生提供参考依据.方法 采用以医院放射科进行X线胸片检查的人员为基础的病例对照研究,病例组为胸片异常的396例病人,对照组为同期没有胸片异常的538例健康体检者.对石材加工所涉及工种的环境用滤膜称重法和滤膜溶解涂片法分别进行总粉尘浓度和粉尘分散度的测定.结果 对照组和病例组粉尘暴露情况差异有显著性[x2=22.32,P<0.05,OR=5.17,95%CI为(2.44,10.91)];抽检的石材加工厂中各工种环境的总粉尘浓度和分散度均符合GBZ2-2002限值的要求.粉尘暴露对X线胸片有影响,危险度随粉尘暴露而增加.吸烟和工龄是胸片异常的危险因素(x2=15.83,4.74; P<0.05);工种对X线胸片异常无显著影响.结论 石材加工工人X线胸片异常与粉尘暴露、吸烟、工龄相关,与工种无关.%Objective To understand the impact of stone processing workers' dust exposures,smoking,length of service and other factors on the chest X-ray abnormalities,and provide a reference for the prevention for the occurrence of related diseases in the industry.Methods A case control study was conducted.396 patients with chest X-ray abnormalities and 538 personnel without chest X-ray abnormalities in the same period as healthy subjects were enrolled.The total dust concentration and dust dispersity of stone processing environment were detected by the membrane filter weighing methods and the membrane filter dissolved smear methods.Results Dust exposures of the control group and the case group were statistically significant,X 2=22.32,p<0.05,OR=5.17,95%CI( 2.44,10.91 ).The total dust concentration and dust dispersity of the stone processing in different work environment were consistent with ( GBZ 2-2002)limit requirements.Dust exposures had an effect on X-ray chest radiograph,and the risk increasd with the

  12. X-ray Pulsars

    CERN Document Server

    Walter, Roland

    2016-01-01

    X-ray pulsars shine thanks to the conversion of the gravitational energy of accreted material to X-ray radiation. The accretion rate is modulated by geometrical and hydrodynamical effects in the stellar wind of the pulsar companions and/or by instabilities in accretion discs. Wind driven flows are highly unstable close to neutron stars and responsible for X-ray variability by factors $10^3$ on time scale of hours. Disk driven flows feature slower state transitions and quasi periodic oscillations related to orbital motion and precession or resonance. On shorter time scales, and closer to the surface of the neutron star, X-ray variability is dominated by the interactions of the accreting flow with the spinning magnetosphere. When the pulsar magnetic field is large, the flow is confined in a relatively narrow accretion column, whose geometrical properties drive the observed X-ray emission. In low magnetized systems, an increasing accretion rate allows the ignition of powerful explosive thermonuclear burning at t...

  13. X-Ray Protection

    Science.gov (United States)

    1955-01-01

    15,000. • When developed In Kodak liquid X-ray developer for 5 min at a temperature of 200 C. b Film sensitivities vary with photon energy by the...for example temporomandibular -joint exposures where a skin dose of 25 r or more may be obtained during a single exposure with 65 kvp, 1.5 mm aluminum...communication. W. J. Updegrave, Temporomandibular articulation-X-ray examina- tion, Dental Radiography and Photography 26, No. 3, 41 (1953). H. 0. Wyckoff, R. J

  14. Chest HRCT findings in acute transformation of adult T-cell lymphoma/leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Fumito; Sato, Haruka; Omeri, Ahmad Khalid; Ono, Asami; Tokuyama, Kouhei; Ando, Yumiko; Matsumoto, Akira; Mori, Hiromu [Oita University Faculty of Medicine, Department of Radiology, Yufu, Oita (Japan); Ogata, Masao; Kohno, Kazuhiro; Takano, Kuniko [Oita University Faculty of Medicine, Department of Medical Oncology and Hematology, Yufu, Oita (Japan)

    2015-06-01

    To assess chest high-resolution computed tomography (HRCT) findings in patients with acute transformation of adult T cell leukaemia/lymphoma (ATLL). We retrospectively identified 72 consecutive patients at our institution with ATLL between October 2000 and March 2014. The cases included acute type (n = 20), lymphoma type (n = 21), smouldering type (n = 24) and chronic type (n = 7). Sixteen (7 men, 9 women; aged 36-85 years, mean 63.3 years) of 31 patients (24 with smouldering and seven with chronic type; 51.6 %) developed acute transformation of ATLL, and had undergone chest HRCT examinations. Parenchymal abnormalities, enlarged lymph nodes, pericardial effusion, pleural effusion and skin lesions were evaluated on HRCT. Chest HRCT of 15 of the 16 patients showed abnormal findings, including ground-glass opacity (GGO) (n = 8), consolidation (n = 5), interlobular septal thickening (n = 5) and nodules (n = 5). Pleural effusion was found in five patients, lymph node enlargement in 10 patients and multiple skin thickening in two patients. Almost all patients with acute transformation of ATLL had abnormal findings on chest HRCT, which consisted mainly of lymph node enlargement, GGO, interlobular septal thickening, nodules and bilateral pleural effusions. (orig.)

  15. Analysis of the X-ray Findings and Etiology of Adolescent Cervical Spondylosis and Prevention Cure%青少年颈椎病X线征象分析及病因与防治探讨

    Institute of Scientific and Technical Information of China (English)

    刘洪涛; 申宝忠; 卜丽红; 何立岩; 金丽莹; 赵世超

    2012-01-01

    Objective: To discuss the X-ray findings of adolescent cervical spondylosis, analyze the etiology of adolescent cervical spondylosis and take out the intervenation therapy. Methods: Clinical and X-ray datas of 87 cases of adolescent cervical spondylosis were collected, the etiology and X-ray findings were analyzed. Results: Adolescent cervical spondylosis were caused by long-time working and studying or badness habits, the intervertebral disc degenerated in advance. The X-ray findings were the changes of curvature and dis-steady. Conclusions: Adolescent cervical spondylosis has typical X-ray findings, and can be avoided by good habits of work and study.%目的:探讨青少年颈椎病的X线征象、针对青少年颈椎病的病因进行分析,并提出相关干预对策.方法:选取本院87例经临床确诊的青少年颈椎病患者的临床及X线资料,对其病因和X线改变进行分析对比.结果:青少年颈椎病是由于长时间低头伏案工作、学习或某些不良习惯使椎间盘长时间处于异常负荷环境下,造成椎间盘提前退变所致,其X线表现主要为颈椎生理曲度改变和颈椎失稳.结论:青少年颈椎病X线平片上具有其特征性,良好的工作、学习、生活习惯可以有效避免青少年颈椎病的发生.

  16. Interpretation of neonatal chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hye Kyung [Dept. of Radiology, Kangwon National University Hospital, Chuncheon (Korea, Republic of)

    2016-05-15

    Plain radiographs for infants in the neonatal intensive care unit are obtained using the portable X-ray equipment in order to evaluate the neonatal lungs and also to check the position of the tubes and catheters used for monitoring critically-ill neonates. Neonatal respiratory distress is caused by a variety of medical or surgical disease conditions. Clinical information about the gestational week, respiratory symptoms, and any events during delivery is essential for interpretation of the neonatal chest radiographs. Awareness of common chest abnormality in the prematurely born or term babies is also very important for chest evaluation in the newborn. Furthermore, knowledge about complications such as air leaks and bronchopulmonary dysplasia following treatment are required to accurately inform the clinicians. The purpose of this article was to briefly review radiographic findings of chest diseases in newborns that are relatively common in daily practice.

  17. Chest computed tomography findings in severe influenza pneumonia occurring in neutropenic cancer patients

    Directory of Open Access Journals (Sweden)

    Rosana Souza Rodrigues

    2012-01-01

    Full Text Available OBJECTIVE: To describe the chest computed tomography findings for severe influenza H1N1 infection in a series of hospitalized neutropenic cancer patients. METHODS: We performed a retrospective systematic analysis of chest computed tomography scans for eight hospitalized patients with fever, neutropenia, and confirmed diagnoses of influenza H1N1. The clinical data had been prospectively collected. RESULTS: Six of eight patients (75% developed respiratory failure and required intensive care. Prolonged H1N1 shedding was observed in the three mechanically ventilated patients, and overall hospital mortality in our series was 25%. The most frequent computed tomography findings were ground-glass opacity (all patients, consolidation (7/8 cases, and airspace nodules (6/8 cases that were frequently moderate or severe. Other parenchymal findings were not common. Five patients had features of pneumonia, two had computed tomography findings compatible with bronchitis and/or bronchiolitis, and one had tomographic signs of chronicity. CONCLUSION: In this series of neutropenic patients with severe influenza H1N1 infection, chest computed tomography demonstrated mainly moderate or severe parenchymatous disease, but bronchiolitis was not a common feature. These findings associated with febrile neutropenia should elicit a diagnosis of severe viral infection.

  18. A Monte Carlo study of x-ray fluorescence in x-ray detectors.

    Science.gov (United States)

    Boone, J M; Seibert, J A; Sabol, J M; Tecotzky, M

    1999-06-01

    Advances in digital x-ray detector systems have led to a renewed interest in the performance of x-ray phosphors and other detector materials. Indirect flat panel x-ray detector and charged coupled device (CCD) systems require a more technologically challenging geometry, whereby the x-ray beam is incident on the front side of the scintillator, and the light produced must diffuse to the back surface of the screen to reach the photoreceptor. Direct detector systems based on selenium have also enjoyed a growing interest, both commercially and academically. Monte Carlo simulation techniques were used to study the x-ray scattering (Rayleigh and Compton) and the more prevalent x-ray fluorescence properties of seven different x-ray detector materials, Gd2O2S, CsI, Se, BaFBr, YTaO4, CaWO4, and ThO2. The redistribution of x-ray energy, back towards the x-ray source, in a forward direction through the detector, and lateral reabsorption in the detector was computed under monoenergetic conditions (1 keV to 130 keV by 1 keV intervals) with five detector thicknesses, 30, 60, 90, 120, and 150 mg/cm2 (Se was studied from 30 to 1000 mg/cm2). The radial distribution (related to the point spread function) of reabsorbed x-ray energy was also determined. Representative results are as follows: At 55 keV, more (31.3%) of the incident x-ray energy escaped from a 90 mg/cm2Gd2O2S detector than was absorbed (27.9%). Approximately 1% of the total absorbed energy was reabsorbed greater than 0.5 mm from the primary interaction, for 90 mg/cm2 CsI exposed at 100 kVp. The ratio of reabsorbed secondary (fluorescence + scatter) radiation to the primary radiation absorbed in the detectors (90 mg/cm2) (S/P) was determined as 10%, 16%, 2%, 12%, 3%, 3%, and 0.3% for a 100 kVp tungsten anode x-ray spectrum, for the Gd2O2S, CsI, Se, BaFBr, YTaO4, CaWO4, and ThO2 detectors, respectively. The results indicate significant x-ray fluorescent escape and reabsorption in common x-ray detectors. These findings

  19. Value of ICU Bedside B-ultrasound and Chest X-ray in the Diagnosis of Traumatic Pneumothorax%重症监护病房床旁B超与胸部X线片检查对创伤性气胸的诊断价值研究

    Institute of Scientific and Technical Information of China (English)

    许庆林; 陈淑娟

    2013-01-01

    目的 比较重症监护病房(ICU)床边B超与胸部X线片检查对创伤性气胸的诊断价值.方法 选取我院ICU收治的84例钝性胸部创伤患者,均行CT检查,随机分为 B超组和X线组,各42例.B超组行床边B超检查,X线组行床边胸部X线片检查,将两组检查结果与CT结果对比.结果 B超组CT检查结果示气胸34例37侧,其中3例为双侧气胸,B超检查结果示气胸26例28侧,其中2例为双侧气胸;X线组CT检查结果示气胸33例35侧,其中2例为双侧气胸,胸部X线片检查结果示气胸25例26侧,其中1例为双侧气胸.B超组和X线组敏感度、特异度、阳性预测值、阴性预测值、准确度比较,差异均无统计学意义(P>0.05).结论 ICU床边B超与胸部X线片诊断气胸敏感性、特异性无显著差异,B超检查方便、无创、可动态观察,方便实用.%Objective To investigate the value of bedside ultrasonography and chest X - ray in the diagnosis of pneumothorax. Methods 84 patients with blunt chest trauma admitted to the ICU of our hospital were given CT examination and were randomly divided into B - ultrasonography group and X - ray group with each group 42 cases. B - ultrasonography group was given bedside B - ultrasonography examination while X - ray group was given bedside chest X - ray examination. The results of the two groups were compared with the CT results. Results In B - ultrasonography group, CT examination results showed 37 sides of pneumothorax in 34 cases and 3 cases were bilateral pneumothorax. While B - ultrasonography examination results showed 28 sides of pneumothorax in 26 cases and 2 cases were bilateral pneumothorax. In X - ray group, CT examination results showed 35 sides of pneumothorax in 33 cases and 2 cases were bilateral pneumothorax. While X - ray examination results showed 26 sides of pneumothorax in 25 cases and one case were bilateral pneumothorax. The sensitivity, specificity, positive predictive value, negative predictive

  20. X-Ray Astronomy

    Science.gov (United States)

    Wu, S. T.

    2000-01-01

    Dr. S. N. Zhang has lead a seven member group (Dr. Yuxin Feng, Mr. XuejunSun, Mr. Yongzhong Chen, Mr. Jun Lin, Mr. Yangsen Yao, and Ms. Xiaoling Zhang). This group has carried out the following activities: continued data analysis from space astrophysical missions CGRO, RXTE, ASCA and Chandra. Significant scientific results have been produced as results of their work. They discovered the three-layered accretion disk structure around black holes in X-ray binaries; their paper on this discovery is to appear in the prestigious Science magazine. They have also developed a new method for energy spectral analysis of black hole X-ray binaries; four papers on this topics were presented at the most recent Atlanta AAS meeting. They have also carried Monte-Carlo simulations of X-ray detectors, in support to the hardware development efforts at Marshall Space Flight Center (MSFC). These computation-intensive simulations have been carried out entirely on the computers at UAH. They have also carried out extensive simulations for astrophysical applications, taking advantage of the Monte-Carlo simulation codes developed previously at MSFC and further improved at UAH for detector simulations. One refereed paper and one contribution to conference proceedings have been resulted from this effort.

  1. X-Ray Background from Early Binaries

    Science.gov (United States)

    Kohler, Susanna

    2016-11-01

    observed X-ray energy (and the total X-ray background is given by the sum of the curves). The two panels show results from two different calculation methods. [Xu et al. 2016]Xu and collaborators have now attempted to model to the impact of this X-ray production from Pop III binaries on the intergalactic medium and determine how much it could have contributed to reionization and the diffuse X-ray background we observe today.Generating a BackgroundThe authorsestimated the X-ray luminosities from Pop III binaries using the results of a series of galaxy-formation simulations, beginning at a redshift of z 25 and evolving up to z = 7.6. They then used these luminosities to calculate the resulting X-ray background.Xu and collaborators find that Pop III binaries can produce significant X-ray radiation throughout the period of reionization, and this radiation builds up gradually into an X-ray background. The team shows that X-rays from Pop III binaries might actually dominate more commonly assumed sources of the X-ray background at high redshifts (such as active galactic nuclei), and this radiation isstrong enough to heat the intergalactic medium to 1000K and ionize a few percent of the neutral hydrogen.If Pop III binaries are indeed this large of a contributor to the X-ray background and to the local and global heating of the intergalactic medium, then its important that we follow up with more detailed modeling to understand what this means for our interpretation of cosmological observations.CitationHao Xu et al 2016 ApJL 832 L5. doi:10.3847/2041-8205/832/1/L5

  2. Accuracy of chest radiography versus chest computed tomography in hemodynamically stable patients with blunt chest trauma

    Directory of Open Access Journals (Sweden)

    Chardoli Mojtaba

    2013-12-01

    Full Text Available 【Abstract】 Objective: Thoracic injuries are respon- sible for 25% of deaths of blunt traumas. Chest X-ray (CXR is the first diagnostic method in patients with blunt trauma. The aim of this study was to detect the accuracy of CXR versus chest computed tomograpgy (CT in hemodynami- cally stable patients with blunt chest trauma. Methods: Study was conducted at the emergency department of Sina Hospital from March 2011 to March 2012. Hemodynamically stable patients with at least 16 years of age who had blunt chest trauma were included. All patients underwent the same diagnostic protocol which consisted of physical examination, CXR and CT scan respectively. Results: Two hundreds patients (84% male and 16% female were included with a mean age of (37.9±13.7 years. Chin J Traumatol 2013;16(6:351-354 Rib fracture was the most common finding of CXR (12.5% and CT scan (25.5%. The sensitivity of CXR for hemothorax, thoracolumbar vertebra fractures and rib fractures were 20%, 49% and 49%, respectively. Pneumothorax, foreign body, emphysema, pulmonary contusion, liver hematoma and ster- num fracture were not diagnosed with CXR alone. Conclusion: Applying CT scan as the first-line diag- nostic modality in hemodynamically stable patients with blunt chest trauma can detect pathologies which may change management and outcome. Key words: Radiography; Thoracic injuries; Tomography, X-ray computed

  3. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... fracture. guide orthopedic surgery, such as spine repair/fusion, joint replacement and fracture reductions. look for injury, ... and Media Arthritis X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to X-ray ( ...

  4. Abdomen X-Ray (Radiography)

    Science.gov (United States)

    ... Professions Site Index A-Z X-ray (Radiography) - Abdomen Abdominal x-ray uses a very small dose ... to produce pictures of the inside of the abdominal cavity. It is used to evaluate the stomach, liver, ...

  5. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... position possible that still ensures x-ray image quality. top of page Who interprets the results and ...

  6. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... patient. top of page How does the procedure work? X-rays are a form of radiation like ... very controlled x-ray beams and dose control methods to minimize stray (scatter) radiation. This ensures that ...

  7. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... radiation like light or radio waves. X-rays pass through most objects, including the body. Once it ... organs, allow more of the x-rays to pass through them. As a result, bones appear white ...

  8. Panoramic Dental X-Ray

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Panoramic Dental X-ray Panoramic dental x-ray uses a ... Your e-mail address: Personal message (optional): Bees: Wax: Notice: RadiologyInfo respects your privacy. Information entered here ...

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... the body. X-rays are the oldest and most frequently used form of medical imaging. A bone ... bones. top of page How should I prepare? Most bone x-rays require no special preparation. You ...

  10. Soft X-ray Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Seely, John

    1999-05-20

    The contents of this report cover the following: (1) design of the soft x-ray telescope; (2) fabrication and characterization of the soft x-ray telescope; and (3) experimental implementation at the OMEGA laser facility.

  11. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... of page What are some common uses of the procedure? A bone x-ray is used to: ... and x-rays. top of page What does the equipment look like? The equipment typically used for ...

  12. Combined bilateral idiopathic necrosis of the humerus and femur heads: Bone scan, X-ray, CT, and MRI findings. Kombinierte beidseitige idiopathische Nekrose der Humerus- und Femurkoepfe: Skelettszintigraphie, Roentgen-, CT- und MRT-Befunde

    Energy Technology Data Exchange (ETDEWEB)

    Piepenburg, R.; Hahn, K. (Mainz Univ. (Germany). Klinik fuer Nuklearmedizin); Doll, G. (Mainz Univ. (Germany). Klinik fuer Roentgendiagnostik); Grimm, J. (Mainz Univ. (Germany). Orthopaedische Klinik)

    1992-12-01

    Untreated aseptic bone necroses close to a joint commonly leads to severe secondary arthrosis and destruction of the joint within a short time. Therefore, only a diagnosis in an early stage of the disease offers the chance of a successful joint- preserving therapy. In cases of clinically suspected aseptic bone necrosis but still negative or doubtful X-ray findings, bone scans or MRI are reliable methods of verifying the diagnosis. (orig./MG).

  13. CT staging of colorectal cancer: What do you find in the chest?

    Energy Technology Data Exchange (ETDEWEB)

    McQueen, A.S., E-mail: andrewmcqueen7@hotmail.com [Department of Radiology, Freeman Hospital, Newcastle upon Tyne (United Kingdom); Scott, J. [Department of Radiology, Freeman Hospital, Newcastle upon Tyne (United Kingdom)

    2012-04-15

    Aim: To clarify the chest computed tomography (CT) findings in patients with a new diagnosis of colorectal adenocarcinoma. Materials and methods: Patients diagnosed with colorectal cancer (CRC) over a 3-year period were retrospectively studied. All CT examinations were performed within a single NHS Trust using the same CT system and protocol. Two primary outcomes were assessed: the presence of pulmonary metastases and the identification of a significant, unexpected chest abnormality. Results: Five hundred and fourteen out of 568 (90.5%) CRC patients underwent complete CT staging. Thirty-one patients (6%) had lung metastases, of which four (0.8%) were isolated. Three hundred and fifty-three (68.7%) had no evidence of pulmonary metastases, but 130 (25.3%) had indeterminate lung nodules (ILNs). The ILNs of 12 patients were subsequently confirmed as metastases on follow-up. A major non-metastatic finding (pulmonary embolism or synchronous primary malignancy) was found in 15/514 patients (3%). Conclusions: Thoracic CT altered the initial TNM stage in fewer than 1% of CRC patients, but the detection of significant incidental chest disease and the establishment of an imaging baseline are useful outcomes of this imaging strategy. One-quarter of all staging examinations demonstrated ILNs.

  14. X-ray Crystallography Facility

    Science.gov (United States)

    2000-01-01

    Edward Snell, a National Research Council research fellow at NASA's Marshall Space Flight Center (MSFC), prepares a protein crystal for analysis by x-ray crystallography as part of NASA's structural biology program. The small, individual crystals are bombarded with x-rays to produce diffraction patterns, a map of the intensity of the x-rays as they reflect through the crystal.

  15. X-Ray Exam: Hip

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Hip KidsHealth > For Parents > X-Ray Exam: Hip A A A What's in ... español Radiografía: cadera What It Is A hip X-ray is a safe and painless test that ...

  16. X-Ray Exam: Finger

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Finger KidsHealth > For Parents > X-Ray Exam: Finger A A A What's in ... español Radiografía: dedo What It Is A finger X-ray is a safe and painless test that ...

  17. X-Ray Exam: Foot

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Foot KidsHealth > For Parents > X-Ray Exam: Foot A A A What's in ... español Radiografía: pie What It Is A foot X-ray is a safe and painless test that ...

  18. X-Ray Exam: Wrist

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Wrist KidsHealth > For Parents > X-Ray Exam: Wrist A A A What's in ... español Radiografía: muñeca What It Is A wrist X-ray is a safe and painless test that ...

  19. X-Ray Exam: Ankle

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Ankle KidsHealth > For Parents > X-Ray Exam: Ankle A A A What's in ... español Radiografía: tobillo What It Is An ankle X-ray is a safe and painless test that ...

  20. X-Ray Exam: Pelvis

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Pelvis KidsHealth > For Parents > X-Ray Exam: Pelvis A A A What's in ... español Radiografía: pelvis What It Is A pelvis X-ray is a safe and painless test that ...

  1. X-Ray Exam: Forearm

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Forearm KidsHealth > For Parents > X-Ray Exam: Forearm A A A What's in ... español Radiografía: brazo What It Is A forearm X-ray is a safe and painless test that ...

  2. Hard X-ray emission from neutron star X-ray binaries

    Energy Technology Data Exchange (ETDEWEB)

    Di Salvo, T.; Santangelo, A.; Segreto, A

    2004-06-01

    In this paper we review our current knowledge of the hard X-ray emission properties of accreting X-ray Binary Pulsars and old accreting neutron stars in Low Mass X-ray Binaries in light of 7 years of BeppoSAX and RXTE observations. The paper is divided in two parts. In the first part we review the more recent findings on the phase-dependent broad band continua and cyclotron resonance scattering features observed in many systems of the X-ray Binary Pulsar class. In the second part we review the hard X-ray emission of LMXRB focussing on the hard X-ray components extending up to energies of a few hundred keV that have been clearly detected in sources of both the atoll and Z classes. The presence and characteristics of these hard emission components are then discussed in relation to source properties and spectral state. We, also, briefly mention models that have been proposed for the hard X-ray emission of neutron star X-ray binaries.

  3. Evaluation of the occupational doses in the ward room of a public hospital of Sergipe, Brazil, during chest X-rays examination;Avaliacao das doses ocupacionais no leito da enfermaria durante exames radiograficos de torax em um hospital publico de Sergipe

    Energy Technology Data Exchange (ETDEWEB)

    Santos, W.S.; Maia, A.F. [Universidade Federal de Sergipe (DF/UFS), Sao Cristovao, SE (Brazil). Dept. de Fisica

    2009-07-01

    Radiology is one of the main tools for medical diagnosis. The substantial growth in the number of radiological interventions is being accompanied by the interest with the patient, technical and clinical body's safety. The use of portable X rays equipment for medical diagnosis in hospitals is a common practice different types of examinations. At ward room, the chest radiography is one of the most requested. During this X ray examination, besides the technical team involved, in the room are also exposed to the scattered radiation. The aim of this study was to evaluate and to quantify the kerma rates, in the air, at different distances of the equipment and to evaluate the doses received by the workers in the ward room of a public hospital. Besides, safe distances were determined for two radiography techniques. Different exams were evaluated and the typical parameters for performing the examination were determined. From that, the kerma rates were measured in the air using a chest phantom. By the results, it was possible to draw a dose map of a ward room of a public hospital of Sergipe. The knowledge of the dose maps allows the technical body to execute the radiological procedures in a safer way, minimizing the risks for them and for the general public. (author)

  4. X-ray today

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, U. [Philips Medical Systems, Hamburg (Germany)

    2001-09-01

    The interest attracted by the new imaging modalities tends to overshadow the continuing importance of projection radiography and fluoroscopy. Nevertheless, projection techniques still represent by far the greatest proportion of diagnostic imaging examinations, and play an essential role in the growing number of advanced interventional procedures. This article describes some of the latest developments in X-ray imaging technology, using two products from the Philips range as examples: the Integris Allura cardiovascular system with 3D image reconstruction, and the BV Pulsera: a high-end, multi-functional mobile C-arm system with cardiac capabilities. (orig.)

  5. SMM x ray polychromator

    Science.gov (United States)

    Saba, J. L. R.

    1993-01-01

    The objective of the X-ray Polychromator (XRP) experiment was to study the physical properties of solar flare plasma and its relation to the parent active region to understand better the flare mechanism and related solar activity. Observations were made to determine the temperature, density, and dynamic structure of the pre-flare and flare plasma as a function of wavelength, space and time, the extent to which the flare plasma departs from thermal equilibrium, and the variation of this departure with time. The experiment also determines the temperature and density structure of active regions and flare-induced changes in the regions.

  6. Echoes in X-ray Binaries

    CERN Document Server

    O'Brien, K; Hynes, R; Chen, W; Haswell, C; Still, M

    2002-01-01

    We present a method of analysing the correlated X-ray and optical/UV variability in X-ray binaries, using the observed time delays between the X-ray driving lightcurves and their reprocessed optical echoes. This allows us to determine the distribution of reprocessing sites within the binary. We model the time-delay transfer functions by simulating the distribution of reprocessing regions, using geometrical and binary parameters. We construct best-fit time-delay transfer functions, showing the regions in the binary responsible for the reprocessing of X-rays. We have applied this model to observations of the Soft X-ray Transient, GRO j1655-40. We find the optical variability lags the X-ray variability with a mean time delay of 19.3$pm{2.2}$ seconds. This means that the outer regions of the accretion disc are the dominant reprocessing site in this system. On fitting the data to a simple geometric model, we derive a best-fit disk half-opening angle of 13.5$^{+2.1}_{-2.8}$ degrees, which is similar to that observe...

  7. Findings chest radiograph and CT in mediastinitis: effcacy of CT in patients with delayed diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Son, Eun Ju; Hong, Yong Kook; Choe, Kyu Ok [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1999-01-01

    To analyse the causes the radiologic findings in patients with mediastinitis and to evaluate the efficacy of chest CT scanning in patients with delayed diagnosis. Seventeen patients with histopathologically(n=15) or clinically diagnosed(n=2) mediastinitis were involved in this study. Eleven of the former group underwent surgery, and in four, tube drainage was performed. All underwent chest radiography and CT scanning, and in seven patients, the causes of delayed diagnosis were analysed. The most common cause of mediastinitis was esophageal rupture(n=11). Others were extension from neck abscess to the mediastinum(n=3), complications after a Benthall procedure(n=1), tuberculous lymphadenitis(n=1) and mycotic aneurysm(n=1). Patients with esophageal rupture suffered from underlying diseases such as esophageal cancer(n=2), iatrogenic esophageal rupture(n=2), Boerhaave's syndrome(n=2), and esophagitis(n=1). In patients with neck abscess (n=3), each was secondary to infected cystic hygroma, Ludwig angina, or deep neck infection, respectively. On chest CT, patients with esophageal rupture(n=11) had an abscess in the posterior mediastinum ; nine abscesses extended to the cervical area along the retropharyngeal space, and the patient with Ludwig angina had an abscess involving all compartments of the mediastinum. Among the total of 17 patients, diagnostic delays were found in seven, while five had spontaneous esophageal ruptures and two suffered complications after a Benthall procedure and Tbc lymphadenitis, respectively. The causes of diagnostic delay varied. Among seven patients, pnevmonia was initially diagnosed in two, who were treated ; one had multiorgan failure, and one was suffering from pericardial effusion and lung abscess. In three other patients, chest radiographs initially showed non-specific findings, leading to delayed CT examination. The most common cause of mediastinitis was esophageal rupture, and in these patients, chest radiographs and clinical

  8. Case of neuro-Behcet syndrome with brainstem lesions confirmed by MRI. Relationship between X-ray CT and MRI findings and neurological symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Takizawa, Shunya; Haida, Munetaka; Ohsuga, Hitoshi; Takagi, Shigeharu; Shinohara, Yukito

    1988-03-01

    A 49-year-old man presented with a 30-year history of oral and genital aphthous ulcers and joint pain. One day before his admission he developed double vision and weakness in the right extremities. Neurological examination revealed right 5th nerve palsy, left 6th to 18th nerve palsy, left Horner's sign, and motor and sensory impairment in the right upper and lower extremities. X-ray CT showed diffuse, weak, low-density areas in the brainstem. T1 weighted images showed low signals in the left side of the mid-pons, the left tegmentum and the right basis of the upper pons, and the left tegmentum of the midbrain. T2 weighted images showed high signals in the whole pons and the left side of the midbrain. MRI allowed the differentiation of reversible lesions, such as brain edema, and irreversible lesions, such as necrosis and demyelination of the tissue. (Namekawa, K.).

  9. Therapeutic options in chronic heart failure. Findings on chest X-ray; Nicht medikamentoese Therapieoptionen der chronischen Herzinsuffizienz. Befunde in der Projektionsradiografie des Thorax

    Energy Technology Data Exchange (ETDEWEB)

    Granitz, M.R.; Meissnitzer, T.; Meissnitzer, M.W.; Hergan, K.; Altenberger, J.; Granitz, C. [Uniklinikum Salzburg - Landeskrankenhaus (Austria)

    2016-05-15

    The contribution covers drugless therapeutic options for chronic heart failure: the implantable cardioverter/defibrillator (ICD), the cardiac resynchronization therapy (CRT), the interventional catheter treatment of functional mitral insufficiency, and mechanical heart supporting systems and heart transplantation.

  10. Topological X-Rays Revisited

    Science.gov (United States)

    Lynch, Mark

    2012-01-01

    We continue our study of topological X-rays begun in Lynch ["Topological X-rays and MRI's," iJMEST 33(3) (2002), pp. 389-392]. We modify our definition of a topological magnetic resonance imaging and give an affirmative answer to the question posed there: Can we identify a closed set in a box by defining X-rays to probe the interior and without…

  11. X-ray instrumentation for SR beamlines

    CERN Document Server

    Kovalchuk, M V; Zheludeva, S I; Aleshko-Ozhevsky, O P; Arutynyan, E H; Kheiker, D M; Kreines, A Y; Lider, V V; Pashaev, E M; Shilina, N Y; Shishkov, V A

    2000-01-01

    The main possibilities and parameters of experimental X-ray stations are presented: 'Protein crystallography', 'X-ray structure analysis', 'High-precision X-ray optics', 'X-ray crystallography and material science', 'X-ray topography', 'Photoelectron X-ray standing wave' that are being installed at Kurchatov SR source by A.V. Shubnikov Institute of Crystallography.

  12. X-ray Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Yano, Junko; Yachandra, Vittal K.

    2009-07-09

    This review gives a brief description of the theory and application of X-ray absorption spectroscopy, both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), especially, pertaining to photosynthesis. The advantages and limitations of the methods are discussed. Recent advances in extended EXAFS and polarized EXAFS using oriented membranes and single crystals are explained. Developments in theory in understanding the XANES spectra are described. The application of X-ray absorption spectroscopy to the study of the Mn4Ca cluster in Photosystem II is presented.

  13. X-ray Fluorescence Sectioning

    CERN Document Server

    Cong, Wenxiang

    2012-01-01

    In this paper, we propose an x-ray fluorescence imaging system for elemental analysis. The key idea is what we call "x-ray fluorescence sectioning". Specifically, a slit collimator in front of an x-ray tube is used to shape x-rays into a fan-beam to illuminate a planar section of an object. Then, relevant elements such as gold nanoparticles on the fan-beam plane are excited to generate x-ray fluorescence signals. One or more 2D spectral detectors are placed to face the fan-beam plane and directly measure x-ray fluorescence data. Detector elements are so collimated that each element only sees a unique area element on the fan-beam plane and records the x-ray fluorescence signal accordingly. The measured 2D x-ray fluorescence data can be refined in reference to the attenuation characteristics of the object and the divergence of the beam for accurate elemental mapping. This x-ray fluorescence sectioning system promises fast fluorescence tomographic imaging without a complex inverse procedure. The design can be ad...

  14. Soft X-ray optics

    CERN Document Server

    Spiller, Eberhard A

    1993-01-01

    This text describes optics mainly in the 10 to 500 angstrom wavelength region. These wavelengths are 50 to 100 times shorter than those for visible light and 50 to 100 times longer than the wavelengths of medical x rays or x-ray diffraction from natural crystals. There have been substantial advances during the last 20 years, which one can see as an extension of optical technology to shorter wavelengths or as an extension of x-ray diffraction to longer wavelengths. Artificial diffracting structures like zone plates and multilayer mirrors are replacing the natural crystals of x-ray diffraction.

  15. Chest CT findings in patients with non-cardiovascular causes of chest pain: Focusing on pulmonary tuberculosis in a tuberculosis endemic country

    Energy Technology Data Exchange (ETDEWEB)

    Lee, So Won; Shim, Sung Shine; Kim, Yoo Kyung; Ryu, Yon Ju [Mokdong Hospital, Ewha Womans University School of Medicine, Seoul (Korea, Republic of)

    2015-10-15

    To review the common causes of non-cardiovascular chest pain (NCCP) according to the location and lesion type as seen on chest CT, and to evaluate CT findings in tuberculosis (TB) as a cause of NCCP. In the period 2009 to 2012, patients having NCCP without definitive evidence of acute myocardial infarction, pulmonary thromboembolism, and aortic dissection, were included. In total, 162 patients (60.5% male; 39.5% female), with a mean age of 51 years, were enrolled. CT images were evaluated by location and lesion type, for causes of NCCP. Chest CT revealed that the most common location for the cause of NCCP was the pleura (45.1%), followed by the subpleural lung parenchyma (30.2%). The most common lesion causing NCCP was TB (33.3%), followed by pneumonia (19.1%). Of the 54 TB cases, 40 (74.1%) were stable TB and 14 (25.9%) were active TB; among these 54 patients, NCCP was most commonly the result of fibrotic pleural thickening (55.6%), followed by subpleural stable pulmonary TB (14.8%). Results of chest CT revealed that TB was a major cause of NCCP in a TB endemic area. Among the TB patients, fibrotic pleural thickening in patients with stable TB was the most common cause of NCCP.

  16. X-ray optics of gold nanoparticles.

    Science.gov (United States)

    Letfullin, Renat R; Rice, Colin E W; George, Thomas F

    2014-11-01

    Gold nanoparticles have been investigated as contrast agents for traditional x-ray medical procedures, utilizing the strong absorption characteristics of the nanoparticles to enhance the contrast of the detected x-ray image. Here we use the Kramers-Kronig relation for complex atomic scattering factors to find the real and imaginary parts of the index of refraction for the medium composed of single-element materials or compounds in the x-ray range of the spectrum. These complex index of refraction values are then plugged into a Lorenz-Mie theory to calculate the absorption efficiency of various size gold nanoparticles for photon energies in the 1-100 keV range. Since the output from most medical diagnostic x-ray devices follows a wide and filtered spectrum of photon energies, we introduce and compute the effective intensity-absorption-efficiency values for gold nanoparticles of radii varying from 5 to 50 nm, where we use the TASMIP model to integrate over all spectral energies generated by typical tungsten anode x-ray tubes with kilovolt potentials ranging from 50 to 150 kVp.

  17. X-ray Polarization in Relativistic Jets

    CERN Document Server

    McNamara, Aimee L; Wu, Kinwah

    2009-01-01

    We investigate the polarization properties of Comptonized X-rays from relativistic jets in Active Galactic Nuclei (AGN) using Monte Carlo simulations. We consider three scenarios commonly proposed for the observed X-ray emission in AGN: Compton scattering of blackbody photons emitted from an accretion disk; scattering of cosmic microwave background (CMB) photons; and self-Comptonization of intrinsically polarized synchrotron photons emitted by jet electrons. Our simulations show that for Comptonization of disk and CMB photons, the degree of polarization of the scattered photons increases with the viewing inclination angle with respect to the jet axis. In both cases the maximum linear polarization is approximately 20%. In the case of synchrotron self-Comptonization (SSC), we find that the resulting X-ray polarization depends strongly on the seed synchrotron photon injection site, with typical fractional polarizations of approximately P = 10 - 20% when synchrotron emission is localized near the jet base, while ...

  18. [What are the tools for post-occupational follow-up, how should they be performed and what are their performance, limits and benefit/risk ratio? Chest X-Ray and CT scan].

    Science.gov (United States)

    Ferretti, G

    2011-06-01

    Chest radiography and computed tomography (CT) are the two radiological techniques used for the follow-up of people exposed to asbestos. Since the last conference of consensus (1999), the scientific literature has primarily covered high-resolution CT and high-resolution volume CT (HR-VCT). We consider in turn the contribution of digital thoracic radiography, recommendations for the performance of HR-VCT to ensure the quality of examination while controlling the delivered radiation dose, and the need to refer to the "CT atlas of benign diseases related to asbestos exposure", published by a group of French experts in 2007, for interpretation. The results of the published studies concerning radiography or CT are then reviewed. We note the great interobserver variability in the recognition of pleural plaques and asbestosis, indicating the need for adequate training of radiologists, and the importance of defining standardized, quantified criteria for CT abnormalities. The very low agreement between thoracic and general radiologists must be taken into account. The reading of CT scans in cases of occupational exposure to asbestos should be entrusted to thoracic radiologists or to general radiologists having validated specific training. A double interpretation of CT could be considered in medicosocial requests. CT is more sensitive than chest radiography in the detection of bronchial carcinoma but generates a great number of false positive results (96 to 99%). No scientific data are available to assess the role of imaging by either CT or chest radiography in the early detection of mesothelioma.

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... bone absorbs much of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x-rays to pass through them. As a result, bones appear white on the x-ray, soft tissue shows up in shades of gray and air ...

  20. X-Ray Diffraction Apparatus

    Science.gov (United States)

    Blake, David F. (Inventor); Bryson, Charles (Inventor); Freund, Friedmann (Inventor)

    1996-01-01

    An x-ray diffraction apparatus for use in analyzing the x-ray diffraction pattern of a sample is introduced. The apparatus includes a beam source for generating a collimated x-ray beam having one or more discrete x-ray energies, a holder for holding the sample to be analyzed in the path of the beam, and a charge-coupled device having an array of pixels for detecting, in one or more selected photon energy ranges, x-ray diffraction photons produced by irradiating such a sample with said beam. The CCD is coupled to an output unit which receives input information relating to the energies of photons striking each pixel in the CCD, and constructs the diffraction pattern of photons within a selected energy range striking the CCD.

  1. Focusing X-Ray Telescopes

    Science.gov (United States)

    O'Dell, Stephen; Brissenden, Roger; Davis, William; Elsner, Ronald; Elvis, Martin; Freeman, Mark; Gaetz, Terrance; Gorenstein, Paul; Gubarev, Mikhall; Jerlus, Diab; Juda, Michael; Kolodziejczak, Jeffrey; Murray, Stephen; Petre, Robert; Podgorski, William; Ramsey, Brian; Reid, Paul; Saha, Timo; Wolk, Scott; Troller-McKinstry, Susan; Weisskopf, Martin; Wilke, Rudeger; Zhang, William

    2010-01-01

    During the half-century history of x-ray astronomy, focusing x-ray telescopes, through increased effective area and finer angular resolution, have improved sensitivity by 8 orders of magnitude. Here, we review previous and current x-ray-telescope missions. Next, we describe the planned next-generation x-ray-astronomy facility, the International X-ray Observatory (IXO). We conclude with an overview of a concept for the next next-generation facility, Generation X. Its scientific objectives will require very large areas (about 10,000 sq m) of highly-nested, lightweight grazing-incidence mirrors, with exceptional (about 0.1-arcsec) resolution. Achieving this angular resolution with lightweight mirrors will likely require on-orbit adjustment of alignment and figure.

  2. X-Ray Tomographic Reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Bonnie Schmittberger

    2010-08-25

    Tomographic scans have revolutionized imaging techniques used in medical and biological research by resolving individual sample slices instead of several superimposed images that are obtained from regular x-ray scans. X-Ray fluorescence computed tomography, a more specific tomography technique, bombards the sample with synchrotron x-rays and detects the fluorescent photons emitted from the sample. However, since x-rays are attenuated as they pass through the sample, tomographic scans often produce images with erroneous low densities in areas where the x-rays have already passed through most of the sample. To correct for this and correctly reconstruct the data in order to obtain the most accurate images, a program employing iterative methods based on the inverse Radon transform was written. Applying this reconstruction method to a tomographic image recovered some of the lost densities, providing a more accurate image from which element concentrations and internal structure can be determined.

  3. X-ray signals in renal osteopathy

    Energy Technology Data Exchange (ETDEWEB)

    Rieden, K.

    1984-10-01

    Chronic renal insufficiency is associated with metabolic disturbances which ultimately lead to typical, partly extremely painful changes in the skeletal system the longer the disease persists. Regular X-ray control of certain skeletal segments allows early detection of renal oesteopathy if the radiological findings described in this article are carefully scrutinised and interpreted.

  4. Comparison of gated radionuclide scans and chest radiographs. Assessment of left ventricular impairment in patients with coronary disease.

    Science.gov (United States)

    Bianco, J A; Reinke, D B; Makey, D G; Shafer, R B

    1980-03-01

    Diagnostic efficacy of gated cardiac blood pool imaging was studied in 41 consecutive patients with LV ejection fractions (LVEF) less than or equal to 0.50. Eighty percent of patients were receiving therapy for LV failure at the time of the study. All patients had documented coronary-artery disease (CAD). Chest x-ray films were interpreted blindly by a senior radiologist. Cardiothoracic ratio of less than or equal to 0.50 was recorded as normal. Radionuclide assessment of LV function contributes importantly to the diagnostic and screening value of chest x-ray films. Patients with coronary disease and clinical evidence of heart failure should have radioisotopic studies even if chest x-ray film findings are normal. In patients with coronary artery disease and enlarged LV on chest films, radionuclide study of left ventricular performance aids in defining LV impairment, and in the prognostication of subsequent clinical course.

  5. X-ray monitoring optical elements

    Energy Technology Data Exchange (ETDEWEB)

    Stoupin, Stanislav; Shvydko, Yury; Katsoudas, John; Blank, Vladimir D.; Terentyev, Sergey A.

    2016-12-27

    An X-ray article and method for analyzing hard X-rays which have interacted with a test system. The X-ray article is operative to diffract or otherwise process X-rays from an input X-ray beam which have interacted with the test system and at the same time provide an electrical circuit adapted to collect photoelectrons emitted from an X-ray optical element of the X-ray article to analyze features of the test system.

  6. X-ray diagnostics for TFTR

    Energy Technology Data Exchange (ETDEWEB)

    von Goeler, S.; Hill, K.W.; Bitter, M.

    1982-12-01

    A short description of the x-ray diagnostic preparation for the TFTR tokamak is given. The x-ray equipment consists of the limiter x-ray monitoring system, the soft x-ray pulse-height-analysis-system, the soft x-ray imaging system and the x-ray crystal spectrometer. Particular attention is given to the radiation protection of the x-ray systems from the neutron environment.

  7. X-ray luminosity functions of different morphological and X-ray type AGN populations

    CERN Document Server

    Pović, M; Sánchez-Portal, M; Bongiovanni, A; Cepa, J; Lorenzo, M Fernández; Lara-López, M A; Gallego, J; Ederoclite, A; Márquez, I; Masegosa, J; Alfaro, E; Castañeda, H; González-Serrano, J I; González, J J; 10.1002/asna.201211840

    2013-01-01

    Luminosity functions are one of the most important observational clues when studying galaxy evolution over cosmic time. In this paper we present the X-ray luminosity functions of X-ray detected AGN in the SXDS and GWS fields. The limiting fluxes of our samples are 9.0x10^(-15) and 4.8x10^(-16) erg/cm^2/sec^(-1) in the 0.5 - 7.0 keV band in the two fields, respectively. We carried out analysis in three X-ray bands and in two redshift intervals up to z < 1.4. Moreover, we derive the luminosity functions for different optical morphologies and X-ray types. We confirm strong luminosity evolution in all three bands, finding the most luminous objects at higher redshift. However, no signs of density evolution are found in any tested X-ray band. We obtain similar results for compact and early-type objects. Finally, we observe the `Steffen effect', where X-ray type-1 sources are more numerous at higher luminosities in comparison with type-2 sources.

  8. Semiconductor X-ray detectors

    CERN Document Server

    Lowe, Barrie Glyn

    2014-01-01

    Identifying and measuring the elemental x-rays released when materials are examined with particles (electrons, protons, alpha particles, etc.) or photons (x-rays and gamma rays) is still considered to be the primary analytical technique for routine and non-destructive materials analysis. The Lithium Drifted Silicon (Si(Li)) X-Ray Detector, with its good resolution and peak to background, pioneered this type of analysis on electron microscopes, x-ray fluorescence instruments, and radioactive source- and accelerator-based excitation systems. Although rapid progress in Silicon Drift Detectors (SDDs), Charge Coupled Devices (CCDs), and Compound Semiconductor Detectors, including renewed interest in alternative materials such as CdZnTe and diamond, has made the Si(Li) X-Ray Detector nearly obsolete, the device serves as a useful benchmark and still is used in special instances where its large, sensitive depth is essential. Semiconductor X-Ray Detectors focuses on the history and development of Si(Li) X-Ray Detect...

  9. Radiation dose and radiation risk to foetuses and newborns during X-ray examinations

    Energy Technology Data Exchange (ETDEWEB)

    Kettunen, A. [Oulu Univ. (Finland)

    2004-05-01

    The purpose of this study is to determine the way in which the demands set by degree 423/2000 by the Ministry of Social Affairs and Health are fulfilled with respect to the most radiosensitive groups, the foetus and the child, by estimating the radiation dose and radiation risk to the foetus from x-ray examinations of an expectant mother's pelvic region, finding out the practice involved in preventing doses to embryos and foetuses and assessing dose practices in cases where an embryo or foetus is or shall be exposed, and by estimating radiation dose and risk due to the radiation received by a new-born being treated in a paediatric intensive care unit. No statistics are available in Finland to indicate how many x-ray examinations of the pelvic region and lower abdomen are made to pregnant patients or to show the dose and risk to the foetus due these examinations. In order to find out the practices in radiological departments concerning the pelvic x-ray examination of fertile woman and the number of foetuses exposed, a questionnaire was sent to all radiation safety officers responsible for the safe use of radiation (n = 290). A total of 173 questionnaires were returned. This study recorded the technique and Dose-Area Product of 118 chest examinations of newborns in paediatric intensive care units. Entrance surface doses and effective doses were calculated separately to each newborn. Based on the patient records, the number of all x-ray examinations during the study was calculated and the effective doses were estimated retrospectively to each child. The radiation risk was estimated both for the foetuses and for the newborns. According to this study, it is rare in Finland to expose a pregnant woman to radiation. On the other hand, with the exception of pelvimetry examinations, there are no compiled statistics concerning the number of pelvic x-ray examinations of a pregnant woman. There was no common practice on how to exclude the possibility of pregnancy. The dose

  10. [X-ray diagnosis of retropatellar diseases (author's transl)].

    Science.gov (United States)

    Wahlers, B

    1979-08-01

    The article reports on a comprehensive, stepwise diagnosis in diseases of the knee joints. This includes a description of the indication, the technique of taking x-ray films, and x-ray findings, as well as arthrography of the femoropatellar joint in retropatellar diseases such as chondropathia patellae, osteochondrosis dissecans, traumas of the knee joints and arthrosis deformans.

  11. X-ray and CT findings of soft tissue and bone infections secondary to acquired immunodeficiency syndrome%艾滋病并发软组织骨骼感染的X线和CT表现

    Institute of Scientific and Technical Information of China (English)

    江松峰; 刘晋新; 陈碧华; 张烈光; 甘清鑫; 黄德扬

    2011-01-01

    Objective To summarize X-ray and CT findings of soft tissue and bone infections secondary to acquired immunodeficiency syndrome (AIDS).Methods The data of X-ray and CT findings of soft tissue and bone infections in 18 patients with AIDS were retrospectively collected and analyzed.Results Of 18 patients with AIDS,the CT features of soft tissue demonstrated that subcutaneous patchy high density in 1 case which considered as cellulitis,round low density lesions with ring enhancement in 6 cases which considered as soft tissue abscesses,heterogeneous density lesions with peripheral enhancement in 1 case which considered as pyomyositis.Of 18 patients with AIDS,septic arthritis was found in 4 cases involving knee lesion in 3 cases and hip lesion.In the 4 case,the X-ray films showed bony destruction in 2 cases and the CT showed bone destruction in 3 cases and arthroedema in 4 cases.Of 18 patients with AIDS,osteomyelitis was found in 9 cases of which tuberculosis was considered in 8 cases and vertebral involvement in 6 cases.In the 9 cases,the X-ray films and CT displayed bony destruction,hyperostosis,small sequestra,and intervertebral space narrowing.Of 18 patients with AIDS,costal lesions were found in 3 cases in which the CT showed expandable bony destruction.Of 18 patients with AIDS,ilium and cacroihac joint lesions were found in 1 case in which the X-ray films and CT showed bony destruction,sequestra,and joint widening.Of 18 patients with AIDS,chronic pyogenic osteomyelitis of femur was found in 1 case in which the X-ray films showed bony destruction,hyperostosis osteosclerosis,and periosteal reaction.Conclusion The X-ray and CT features of soft tissue and bone infections secondary to AIDS are characterized.The X-ray and CT are useful tools to early diagnose soft tissue and bone infections secondary to AIDS.%目的 探讨艾滋病(AIDS)并发软组织骨骼感染的X线和CT表现.方法 回顾性分析18例AIDS并发软组织骨骼感染的X线和CT表现.结果 18

  12. X-ray Properties of an Unbiased Hard X-ray Detected Sample of AGN

    Science.gov (United States)

    Winter, Lisa M.; Mushotzky, Richard F.; Tueller, Jack; Markwardt, Craig

    2007-01-01

    The SWIFT gamma ray observatory's Burst Alert Telescope (BAT) has detected a sample of active galactic nuclei (AGN) based solely on their hard X-ray flux (14-195keV). In this paper, we present for the first time XMM-Newton X-ray spectra for 22 BAT AGXs with no previously analyzed X-ray spectra. If our sources are a representative sample of the BAT AGN, as we claim, our results present for the first time global X-ray properties of an unbiased towards absorption (n(sub H) = 0.03), AGN sample. We find 9/22 low absorption (n(sub H) 2.0 keV. Five of the complex sources (NGC 612, ESO 362-G018, MRK 417, ESO 506-G027, and NGC 6860) are classified as Compton-thick candidates. Further, we find four more sources (SWIFT J0641.3+3257, SWIFT J0911.2+4533, SWIFT J1200.8+0650, and NGC 4992) with properties consistent with the hidden/buried AGN reported by Ueda et al. (2007). Finally, we include a comparison of the XMM EPIC spectra with available SWIFT X-ray Telescope (XRT) observations. From these comparisons, we find 6/16 sources with varying column densities, 6/16 sources with varying power law indices, and 13/16 sources with varying fluxes, over periods of hours to months. Flux and power law index are correlated for objects where both parameters vary.

  13. X射线胸部摄影曝光剂量与图像质量相关性研究%Study on correlation between exposure dose and image quality of X-ray chest radiography

    Institute of Scientific and Technical Information of China (English)

    曹允希; 蔡小涛; 谢晋东; 曹鑫

    2014-01-01

    Objective To investigate optimal radiation dose for digital radiography by researching the correlation between radiation dose and image quality of high kV chest radiography.Methods The kV of chest radiography was setted on 120 kV while mAs was changed.The chest radiography phantom and the contrast detail phantom CDRAD2.0 were exposed by DR with different mAs from 1 to 25 mAs.The entrance doses were measured for all exposures and the images were read independently by 5 observers on a higher resolution monitor of diagnosis work station.The image quality figure (IQF) was measured for each image.Comparison of the mean IQFs with different exposure doses were conducted in order to determined which was the optimal exposure condition for high kV radiography.The image quality of normal adult using different mAs,4 and 10 mAs for high KV chest radiography was compared.Results When the mAs was increased from 1 to 25 mAs,the entrance doses varied from 0.067 to 1.468 mGy.With the entrance doses increasing,the value of IQF was decreased (F =31.00,P < 0.05).The values of IQF were statistically different between 1 and 4 mAs(F =15.3,P <0.05),and between 10 and 25 mAs(F =9.74,P <0.05).At 4 and 10 mAs with the entrance dose 0.250 and 0.606 mGy,the synthesis score of chest high kV radiography from two kinds of exposure dose was (24.8 ± 1.64),(25.8 ± 2.05),with no statistically significant difference.Conclusions For digital radiography,increasing radiation dose can improve image information.The optimal entrance dose of high kV chest radiography for standard body was about 0.250 mGy.%目的 研究数字化X射线胸部高千伏摄影曝光剂量与图像质量的关系,确定数字化X射线摄影最佳曝光剂量.方法 选择胸部高千伏摄影管电压120 kV,摄影mAs从1 mAs逐档增加至25 mAs,对模拟人体胸部厚度摄影体模与CDRAD 2.0对比度细节体模进行摄影,测量体模表面X射线入射剂量,由5位观察者独立阅读体模影像,比较任意两

  14. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... are easily accessible and are frequently compared to current x-ray images for diagnosis and disease management. ... of North America, Inc. (RSNA). To help ensure current and accurate information, we do not permit copying ...

  15. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... patients and physicians. Because x-ray imaging is fast and easy, it is particularly useful in emergency ... diagnosis and treatment of the individual patient's condition. Ultrasound imaging, which uses sound waves instead of ionizing ...

  16. X-Ray Assembler Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — Federal regulations require that an assembler who installs one or more certified components of a diagnostic x-ray system submit a report of assembly. This database...

  17. CELESTIAL X-RAY SOURCES.

    Science.gov (United States)

    sources, (4) the physical conditions in the pulsating x-ray source in the Crab Nebula , and (5) miscellaneous related topics. A bibliography of all work performed under the contract is given. (Author)

  18. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... ionizing radiation to produce pictures of any bone in the body. It is commonly used to diagnose ... bone x-ray makes images of any bone in the body, including the hand, wrist, arm, elbow, ...

  19. Bone X-Ray (Radiography)

    Science.gov (United States)

    ... bony fragments following treatment of a fracture. guide orthopedic surgery, such as spine repair/fusion, joint replacement ... A portable x-ray machine is a compact apparatus that can be taken to the patient in ...

  20. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | Site Map Copyright © 2017 Radiological ...

  1. Accelerator x-ray sources

    CERN Document Server

    Talman, Richard

    2007-01-01

    This first book to cover in-depth the generation of x-rays in particle accelerators focuses on electron beams produced by means of the novel Energy Recovery Linac (ERL) technology. The resulting highly brilliant x-rays are at the centre of this monograph, which continues where other books on the market stop. Written primarily for general, high energy and radiation physicists, the systematic treatment adopted by the work makes it equally suitable as an advanced textbook for young researchers.

  2. X-ray fluorescence holography

    CERN Document Server

    Hayashi, K; Takahashi, Y

    2003-01-01

    X-ray fluorescence holography (XFH) is a new structural analysis method of determining a 3D atomic arrangement around fluorescing atoms. We developed an XFH apparatus using advanced X-ray techniques and succeeded in obtaining high-quality hologram data. Furthermore, we introduced applications to the structural analysis of a thin film and the environment around dopants and, discussed the quantitative analysis of local lattice distortion. (author)

  3. X-ray laser; Roentgenlaser

    Energy Technology Data Exchange (ETDEWEB)

    Samuelsen, Emil J.; Breiby, Dag W.

    2009-07-01

    X-ray is among the most important research tools today, and has given priceless contributions to all disciplines within the natural sciences. State of the art in this field is called XFEL, X-ray Free Electron Laser, which may be 10 thousand million times stronger than the x-rays at the European Synchrotron Radiation Facility in Grenoble. In addition XFEL has properties that allow the study of processes which previously would have been impossible. Of special interest are depictions on atomic- and molecular level by the use of x-ray holographic methods, and being able to study chemical reactions in nature's own timescale, the femtosecond. Conclusion: The construction of x-ray lasers is a natural development in a scientific field which has an enormous influence on the surrounding society. While the discovery of x-ray was an important breakthrough in itself, new applications appear one after the other: Medical depiction, dissemination, diffraction, DNA and protein structures, synchrotron radiation and tomography. There is reason to believe that XFEL implies a technological leap as big as the synchrotrons some decades ago. As we are now talking about studies of femtosecond and direct depiction of chemical reactions, it is obvious that we are dealing with a revolution to come, with extensive consequences, both scientifically and culturally. (EW)

  4. Outbursts in ultracompact X-ray binaries

    CERN Document Server

    Hameury, J -M

    2016-01-01

    Very faint X-ray binaries appear to be transient in many cases with peak luminosities much fainter than that of usual soft X-ray transients, but their nature still remains elusive. We investigate the possibility that this transient behaviour is due to the same thermal/viscous instability which is responsible for outbursts of bright soft X-ray transients, occurring in ultracompact binaries for adequately low mass-transfer rates. More generally, we investigate the observational consequences of this instability when it occurs in ultracompact binaries. We use our code for modelling the thermal-viscous instability of the accretion disc, assumed here to be hydrogen poor. We also take into account the effects of disc X-ray irradiation, and consider the impact of the mass-transfer rate on the outburst brightness. We find that one can reproduce the observed properties of both the very faint and the brighter short transients (peak luminosity, duration, recurrence times), provided that the viscosity parameter in quiesce...

  5. X-Rays, Pregnancy and You

    Science.gov (United States)

    ... and Procedures Medical Imaging Medical X-ray Imaging X-Rays, Pregnancy and You Share Tweet Linkedin Pin ... the decision with your doctor. What Kind of X-Rays Can Affect the Unborn Child? During most ...

  6. Accuracy of chest radiography versus chest computed tomography in hemodynamically stable patients with blunt chest trauma

    Institute of Scientific and Technical Information of China (English)

    Mojtaba Chardoli; Toktam Hasan-Ghaliaee; Hesam Akbari; Vafa Rahimi-Movaghar

    2013-01-01

    Objective:Thoracic injuries are responsible for 25% of deaths of blunt traumas.Chest X-ray (CXR) is the first diagnostic method in patients with blunt trauma.The aim of this study was to detect the accuracy of CXR versus chest computed tomograpgy (CT) in hemodynamically stable patients with blunt chest trauma.Methods:Study was conducted at the emergency department of S ina Hospital from March 2011 to March 2012.Hemodynamically stable patients with at least 16 years of age who had blunt chest trauma were included.All patients underwent the same diagnostic protocol which consisted of physical examination,CXR and CT scan respectively.Results:Two hundreds patients (84% male and 16% female) were included with a mean age of(37.9±13.7) years.Rib fracture was the most common finding of CXR (12.5%) and CT scan (25.5%).The sensitivity of CXR for hemothorax,thoracolumbar vertebra fractures and rib fractures were 20%,49% and 49%,respectively.Pneumothorax,foreign body,emphysema,pulmonary contusion,liver hematoma and sternum fracture were not diagnosed with CXR alone.Conclusion:Applying CT scan as the first-line diagnostic modality in hemodynamically stable patients with blunt chest trauma can detect pathologies which may change management and outcome.

  7. Lung parenchymal change after the resolution of adenovirus pneumonia : chest radiographs and high-resolution CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jung Hee; Kim, Joung Sook; Kim, Chang Kuen; Kang, Seung Pyung; Lee, Soo Hyun; Hur Gham [Inje Univ. Sanggye Paik Hospital, Seoul (Korea, Republic of)

    1998-07-01

    To evaluate lung parenchymal change as seen on chest radiographs and high-resolution CT (HRCT) after the resolution of adenovirus pneumonia (a common cause of lower respiratory infection in infants and children),and the usefulness of HRCT during follow-up. Material and Methods : Four to 13(mean, 8) months after recovery, ten patients infected with adenovirus pneumonia underwent HRCT and chest radiographs. Eight were boys and two were girls, and their mean age was 26(range, 14-45) months. Adenovirus pneumonia had been confirmed by viral isolation in culture or serologic test. CT scanning was performed during quiet breathing ; collimation was 2 mm and the interval from apex to diaphragm was 5-10 mm. Lung settings were 1600 HU (window width) and -700 HU(level). CT findings were assessed and compared with chest radiographs by two chest radiologists, who reached a consensus. The patients were clinically followed up for one year. Result : On chest radiographs, hyperlucent lung was seen in 8 of 10 patients (80%) ; in one other there was partial collapse, and in one, findings were normal. The most common HRCT finding was a mosaic pattern of lung attenuation with decreased pulmonary vascularity in the area of lower attenuation ; this was seen in 8 of 10 patients (80%). Other findings were partial collapse, bronchiectasis, and bronchial wall thickening, each seen in two patients, and reticulonodular density, seen in one. In two patients HRCT findings were normal ; in one of these, chest findings were normal but a mosaic pattern of lung attenuation was found in all lobes. During follow-up, three patients wheezed continuously. Conclusion : In cases of adenovirus pneumonia, HRCT demonstrated more specific parenchymal change than did chest radiographs ; a mosaic pattern of lung attenuation was seen, with decreased pulmonary vascularity in areas of lower attenuation ; bronchiectasis,bronchial wall thickening, and reticulo-odular density were also noted. These findings were

  8. Incidental finding of unilateral isolated aplasia of serratus anterior muscle and winged scapula on chest radiograph: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Joon Sung; Park, Hyun Jin; Ko, Jeong Min [Dept. of Radiology, St. Vincent' s Hospital, College of Medicine, The Catholic University of Korea, Suwon (Korea, Republic of)

    2014-10-15

    The isolated aplasia of the serratus anterior muscle with winging of scapula is very rare, and only a few cases are reported. Here, we present a case of a 30-year-old Korean male who initially presented with a left flank pain. His physical exam did not show any significant finding in his right shoulder. However, his chest radiograph showed absence of right serratus anterior muscle and slightly elevated and medially rotated right scapula. Subsequent CT scan showed the right serratus anterior muscle aplasia and medial winging of the right scapula. This case is unique in two aspects. First, the combination of abnormalities is different from the typical congenital abnormalities involving shoulder girdle, such as Sprengel deformity or Poland syndrome. Secondly, this was incidentally diagnosed with chest radiograph, without clinical impression. Careful reading of chest radiograph can help the radiologists to detect such clinically silent abnormalities.

  9. SZ/X-ray scaling relations using X-ray data and Planck Nominal maps

    Science.gov (United States)

    De Martino, I.; Atrio-Barandela, F.

    2016-09-01

    We determine the relation between the Comptonization parameter predicted using X-ray data YC, Xray and the X-ray luminosity LX, both magnitudes derived from ROSAT data, with the Comptonization parameter YC, SZ measured on Planck 2013 foreground cleaned Nominal maps. The 560 clusters of our sample includes clusters with masses M ≥ 1013 M⊙, one order of magnitude smaller than those used by the Planck Collaboration in a similar analysis. It also contains eight times more clusters in the redshift interval z ≤ 0.3. The prediction of the β = 2/3 model convolved with the Planck antenna beam agrees with the anisotropies measured in foreground cleaned Planck Nominal maps within the X-ray emitting region, confirming the results of an earlier analysis. The universal pressure profile overestimates the signal by a 15-21 per cent depending on the angular aperture. We show that the discrepancy is not due to the presence of cool-core systems but it is an indication of a brake in the LX - M relation towards low mass systems. We show that relation of the Comptonization parameter averaged over the region that emits 99 per cent of the X-ray flux and and the X-ray luminosity is consistent with the predictions of the self-similar model. We confirm previous findings that the scaling relations studied here do not evolve with redshift within the range probed by our catalogue.

  10. X-ray Echo Spectroscopy.

    Science.gov (United States)

    Shvyd'ko, Yuri

    2016-02-26

    X-ray echo spectroscopy, a counterpart of neutron spin echo, is being introduced here to overcome limitations in spectral resolution and weak signals of the traditional inelastic x-ray scattering (IXS) probes. An image of a pointlike x-ray source is defocused by a dispersing system comprised of asymmetrically cut specially arranged Bragg diffracting crystals. The defocused image is refocused into a point (echo) in a time-reversal dispersing system. If the defocused beam is inelastically scattered from a sample, the echo signal acquires a spatial distribution, which is a map of the inelastic scattering spectrum. The spectral resolution of the echo spectroscopy does not rely on the monochromaticity of the x rays, ensuring strong signals along with a very high spectral resolution. Particular schemes of x-ray echo spectrometers for 0.1-0.02 meV ultrahigh-resolution IXS applications (resolving power >10^{8}) with broadband ≃5-13  meV dispersing systems are introduced featuring more than 10^{3} signal enhancement. The technique is general, applicable in different photon frequency domains.

  11. X-ray Echo Spectroscopy

    Science.gov (United States)

    Shvyd'ko, Yuri

    2016-02-01

    X-ray echo spectroscopy, a counterpart of neutron spin echo, is being introduced here to overcome limitations in spectral resolution and weak signals of the traditional inelastic x-ray scattering (IXS) probes. An image of a pointlike x-ray source is defocused by a dispersing system comprised of asymmetrically cut specially arranged Bragg diffracting crystals. The defocused image is refocused into a point (echo) in a time-reversal dispersing system. If the defocused beam is inelastically scattered from a sample, the echo signal acquires a spatial distribution, which is a map of the inelastic scattering spectrum. The spectral resolution of the echo spectroscopy does not rely on the monochromaticity of the x rays, ensuring strong signals along with a very high spectral resolution. Particular schemes of x-ray echo spectrometers for 0.1-0.02 meV ultrahigh-resolution IXS applications (resolving power >108 ) with broadband ≃5 - 13 meV dispersing systems are introduced featuring more than 103 signal enhancement. The technique is general, applicable in different photon frequency domains.

  12. X-ray echo spectroscopy

    CERN Document Server

    Shvyd'ko, Yuri

    2015-01-01

    X-ray echo spectroscopy, a counterpart of neutron spin-echo, is being introduced here to overcome limitations in spectral resolution and weak signals of the traditional inelastic x-ray scattering (IXS) probes. An image of a point-like x-ray source is defocused by a dispersing system comprised of asymmetrically cut specially arranged Bragg diffracting crystals. The defocused image is refocused into a point (echo) in a time-reversal dispersing system. If the defocused beam is inelastically scattered from a sample, the echo signal acquires a spatial distribution, which is a map of the inelastic scattering spectrum. The spectral resolution of the echo spectroscopy does not rely on the monochromaticity of the x-rays, ensuring strong signals along with a very high spectral resolution. Particular schemes of x-ray echo spectrometers for 0.1--0.02-meV ultra-high-resolution IXS applications (resolving power $> 10^8$) with broadband $\\simeq$~5--13~meV dispersing systems are introduced featuring more than $10^3$ signal e...

  13. Incoherent x-ray scattering in single molecule imaging

    CERN Document Server

    Slowik, Jan Malte; Dixit, Gopal; Jurek, Zoltan; Santra, Robin

    2014-01-01

    Imaging of the structure of single proteins or other biomolecules with atomic resolution would be enormously beneficial to structural biology. X-ray free-electron lasers generate highly intense and ultrashort x-ray pulses, providing a route towards imaging of single molecules with atomic resolution. The information on molecular structure is encoded in the coherent x-ray scattering signal. In contrast to crystallography there are no Bragg reflections in single molecule imaging, which means the coherent scattering is not enhanced. Consequently, a background signal from incoherent scattering deteriorates the quality of the coherent scattering signal. This background signal cannot be easily eliminated because the spectrum of incoherently scattered photons cannot be resolved by usual scattering detectors. We present an ab initio study of incoherent x-ray scattering from individual carbon atoms, including the electronic radiation damage caused by a highly intense x-ray pulse. We find that the coherent scattering pa...

  14. Chest radiography and thoracic computed tomography findings in children who have family members with active pulmonary tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Uzum, Kazim; Karahan, Okkes I.; Dogan, Sukru; Coskun, Abdulhakim E-mail: coskuna@erciyes.edu.tr; Topcu, Faik

    2003-12-01

    Objective: The chest radiography and TCT findings in children who had contacted with adult family members with active pulmonary tuberculosis were compared. The contributions of thoracic computed tomography to the diagnosis of tuberculosis were investigated. Methods and material: The children who were 0-16 years old (n=173) and children of families with an adult member which was diagnosed as pulmonary tuberculosis were evaluated. The children were considered in two groups based on the absence (n=125) or presence (n=48) of complaints and/or ambiguous symptoms such as lack of appetite, mild cough, sweating, history of lung infection, low body weight and those with suspicious chest radiography findings (12 cases) were included in this study. Asymptomatic patients (n=125) did not undergo TCT. Patients who had positive PPD skin tests only received isoniazid. If the TCT demonstrated enlarged lymph nodes or parenchymal lesions, minimally active pulmonary tuberculosis was diagnosed and antituberculous treatment was given. Results and discussions: TCT revealed lymph node enlargement or parenchymal lesions in 39 children (81.2%). Of the 12 children whose CXRs revealed suspicious lymph node enlargement and/or infiltration, five had normal findings in TCT whereas the initial findings were confirmed in the remaining seven. These data suggest that there is a correlation between the presence of ambiguous symptoms in exposed children and TCT findings; chest radiography and TCT findings do not yield parallel findings. All the patients who received anti-TB treatment were resolved in the control examinations. Conclusion: In this study there is a correlation between presence of ambiguous symptoms and TCT findings, but the chest radiography and TCT findings do not yield harmony in exposed children with ambiguous symptoms (suspicious tuberculosis cases). These observations should be considered in children with symptoms similar to those of exposed children, but with no definite history of

  15. X-ray Photoevaporation-starved T Tauri Accretion

    CERN Document Server

    Drake, Jeremy J; Flaccomio, Ettore; Micela, Giusi

    2009-01-01

    X-ray luminosities of accreting T Tauri stars are observed to be systematically lower than those of non-accretors. There is as yet no widely accepted physical explanation for this effect, though it has been suggested that accretion somehow suppresses, disrupts or obscures coronal X-ray activity. Here, we suggest that the opposite might be the case: coronal X-rays modulate the accretion flow. We re-examine the X-ray luminosities of T Tauri stars in the Orion Nebula Cluster and find that not only are accreting stars systematically fainter, but that there is a correlation between mass accretion rate and stellar X-ray luminosity. We use the X-ray heated accretion disk models of Ercolano et al. to show that protoplanetary disk photoevaporative mass loss rates are strongly dependent on stellar X-ray luminosity and sufficiently high to be competitive with accretion rates. X-ray disk heating appears to offer a viable mechanism for modulating the gas accretion flow and could be at least partially responsible for the o...

  16. Quantum effets in nonresonant X-ray scattering

    Energy Technology Data Exchange (ETDEWEB)

    Slowik, Jan Malte

    2015-11-15

    experiments. In the quantum theory it has however been revealed that X-ray scattering patterns of electronic motion are related to complex spatio-temporal correlations, instead of the instantaneous electron density. I scrutinize the time-resolved scattering pattern from coherent electronic wave packets. I show that timeresolved PCI recovers the instantaneous electron density of electronic motion. For the far-field diffraction scattering pattern, I analyze the influence of photon energy resolution of the detector. Moreover, I demonstrate that X-ray scattering from a crystal of identical wave packets also recovers the instantaneous electron density. I point out that a generalized electron density propagator of the wave packet can be reconstructed from a scattering experiment. Finally, I propose timeresolved Compton scattering of electronic wave packets. I show that X-ray scattering with large energy transfer can be used to recover the instantaneous momentum space density of the target. The third topic of this dissertation is Compton scattering in single molecule coherent diffractive imaging (CDI). The structure determination of single macromolecules via CDI is one of the key applications of XFELs. The structure of the molecule can be reconstructed from the elastic diffraction pattern. Inelastic X-ray scattering generates a background signal, which I determine for typical high-intensity imaging conditions. I find that at high X-ray fluence the background signal becomes dominating, posing a problem for high resolution imaging. The strong ionization by the X-ray pulse may ionize several electrons per atom. Scattering from these free electrons makes a major contribution to the background signal. I present and discuss detailed numerical studies for different X-ray fluence and photon energy.

  17. A study on findings from simple chest radiographs without any clinical symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ham Gyum [Ansan College, Ansan (Korea, Republic of)

    2007-06-15

    In this study, the analysis on findings from simple chest radiography (CXR) test with total 1,669 subjects without any special clinical symptom came to the following conclusions: In terms of the general characteristics of subjects hereof, male and female group accounted for 55.2% and 44.8% respectively out of all 1,669 people. Pulmonary disease cases amounted to 249 persons (14.9%) out of all subjects. In the analysis on prevalence rate by age distribution, it was noted that the older age led to the more number of diseases, which was demonstrated by age 34 or younger (6.1%), age 35 {approx} 39 (9.7%), age 40 {approx} 49 (13.3%), and age 50 or older (30.8%). In regard of pulmonary disease alone, the region of onset was represented primarily by right upper lobe, which was followed by both upper lobe and left upper lobe, respectively. In terms of disease types, it was found that most cases were represented by pulmonary nodule (55.0%), which was followed by cardiomegaly (24.5%), CP angle blunting (4.8%), scoliosis (4.6%) tortuous aorta (2.8%), bronchial luminal dilatation(2.4%), and pleural thickening (2.0%). However, dextrocardia, cystic dilation of bronchus, cavitary lesion, and lung collapse accounted for relatively low rate (0.4% respectively). In terms of disease types by sex, it was found that male group accounted for higher percentage of having cardiomegaly, tortuous aorta and scoliosis than the former. In terms of disease types by age distribution, it was noted that age 34 or younger group accounted for higher percentage of scoliosis than any other age groups, while age 40 {approx} 49 group, age 35 {approx} 39 group, and age 50 or older group represented the case of CP angle blunting, pulmonary nodule, and cardiomegaly/tortuous aorta, respectively.

  18. X-ray imaging: Perovskites target X-ray detection

    Science.gov (United States)

    Heiss, Wolfgang; Brabec, Christoph

    2016-05-01

    Single crystals of perovskites are currently of interest to help fathom fundamental physical parameters limiting the performance of perovskite-based polycrystalline solar cells. Now, such perovskites offer a technology platform for optoelectronic devices, such as cheap and sensitive X-ray detectors.

  19. High-resolution computed tomography in silicosis: correlation with chest radiography and pulmonary function tests

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Agnaldo Jose [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Pedro Ernesto Univ. Hospital. Dept. of Respiratory Function]. E-mail: phel.lop@uol.com.br; Mogami, Roberto; Capone, Domenico; Jansen, Jose Manoel [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). School of Medical Sciences; Tessarollo, Bernardo [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. of Radiology and Diagnostic Image; Melo, Pedro Lopes de [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. of Biology

    2008-05-15

    Objective: To correlate tomographic findings with pulmonary function findings, as well as to compare chest X-ray findings with high-resolution computed tomography (HRCT) findings, in patients with silicosis. Methods: A cross-sectional study was conducted in 44 non-smoking patients without a history of tuberculosis. Chest X-ray findings were classified according to the International Labour Organization recommendations. Using a semiquantitative system, the following HRCT findings were measured: the full extent of pulmonary involvement; parenchymal opacities; and emphysema. Spirometry and forced oscillation were performed. Pulmonary volumes were evaluated using the helium dilution method, and diffusing capacity of the lung for carbon monoxide was assessed. Results: Of the 44 patients studied, 41 were male. The mean age was 48.4 years. There were 4 patients who were classified as category 0 based on X-ray findings and as category 1 based on HRCT findings. Using HRCT scans, we identified progressive massive fibrosis in 33 patients, compared with only 23 patients when X-rays were used. Opacity score was found to correlate most closely with airflow, DLCO and compliance. Emphysema score correlated inversely with volume, DLCO and airflow. In this sample of patients presenting a predominance of large opacities (75% of the individuals), the deterioration of pulmonary function was associated with the extent of structural changes. Conclusions: In the early detection of silicosis and the identification of progressive massive fibrosis, HRCT scans are superior to X-rays. (author)

  20. X-ray focusing using microchannel plates

    Science.gov (United States)

    Kaaret, P.; Geissbuehler, P.; Chen, A.; Glavinas, E.

    1992-01-01

    We present measurements of the X-ray focusing properties of square-pore microchannel plates (MCP's). Square-pore MCP's contain large numbers of closely packed optical surfaces, as required for grazing incidence X-ray optics. The surface of individual MCP channels has been measured and found to have high microroughness transverse to the channel axis and low microroughness parallel to the axis. The high frequency transverse roughness, on length scales greater than 400 nm, has a rms value of 5.9 nm and a Gaussian autocorrelation function with correlation length of 1.41 micron. We find that the geometric misalignments of the surfaces of different channels limit the angular resolution obtainable with current samples of MCP's to 7.1 arcmin.

  1. Bedside chest radiography of novel influenza A (H7N9) virus infections and follow-up findings after short-time treatment

    Institute of Scientific and Technical Information of China (English)

    SONG Feng-xiang; ZHOU Jun; SHI Yu-xin; ZHANG Zhi-yong; FENG Feng; ZHOU Jian-jun; WANG Qing-le

    2013-01-01

    Background Influenza A (H7Ng) virus infections were first observed in China in March 2013.This type virus can cause severe illness and deaths,the situation raises many urgent questions and global public health concerns.Our purpose was to investigate bedside chest radiography findings for patients with novel influenza A (H7Ng) virus infections and the followup appearances after short-time treatment.Methods Eight hospitalized patients infected with the novel influenza A (H7Ng) virus were included in our study.All of the patients underwent bedside chest radiography after admission,and all had follow-up bedside chest radiography during their first ten days,using AXIOM Aristos MX and/or AMX-Ⅳ portable X-ray units.The exposure dose was generally 90 kV and 5 mAs,and was slightly adjusted according to the weight of the patients.The initial radiography data were evaluated for radiological patterns (ground glass opacity,consolidation,and reticulation),distribution type (focal,multifocal,and diffuse),lung zones involved,and appearance at follow-up while the patients underwent therapy.Results All patients presented with bilateral multiple lung involvement.Two patients had bilateral diffuse lesions,three patients had unilateral diffuse lesions of the right lobe with multifocal lesions of the left lobe,and the remaining three had bilateral multifocal lung lesions.The lesions were present throughout bilateral lung zones in three patients,the whole right lung zone in three patients with additional involvement in the left middle and/or lower lung zone(s),both lower and middle lung zones in one patient,and the right middle and lower in combination with the left lower lung zones in one patient.The most common abnormal radiographic patterns were ground glass opacity (8/8),and consolidation (8/8).In three cases examined by CT we also found the pattern of reticulation in combination with CT images.Four patients had bilateral and four had unilateral pleural effusion.After a short

  2. Anisotropic imaging performance in indirect x-ray imaging detectors.

    Science.gov (United States)

    Badano, Aldo; Kyprianou, Iacovos S; Sempau, Josep

    2006-08-01

    We report on the variability in imaging system performance due to oblique x-ray incidence, and the associated transport of quanta (both x rays and optical photons) through the phosphor, in columnar indirect digital detectors. The analysis uses MANTIS, a combined x-ray, electron, and optical Monte Carlo transport code freely available. We describe the main features of the simulation method and provide some validation of the phosphor screen models considered in this work. We report x-ray and electron three-dimensional energy deposition distributions and point-response functions (PRFs), including optical spread in columnar phosphor screens of thickness 100 and 500 microm, for 19, 39, 59, and 79 keV monoenergetic x-ray beams incident at 0 degrees, 10 degrees, and 15 degrees. In addition, we present pulse-height spectra for the same phosphor thickness, x-ray energies, and angles of incidence. Our results suggest that the PRF due to the phosphor blur is highly nonsymmetrical, and that the resolution properties of a columnar screen in a tomographic, or tomosynthetic imaging system varies significantly with the angle of x-ray incidence. Moreover, we find that the noise due to the variability in the number of light photons detected per primary x-ray interaction, summarized in the information or Swank factor, is somewhat independent of thickness and incidence angle of the x-ray beam. Our results also suggest that the anisotropy in the PRF is not less in screens with absorptive backings, while the noise introduced by variations in the gain and optical transport is larger. Predictions from MANTIS, after additional validation, can provide the needed understanding of the extent of such variations, and eventually, lead to the incorporation of the changes in imaging performance with incidence angle into the reconstruction algorithms for volumetric x-ray imaging systems.

  3. Nanofocusing refractive X-ray lenses

    Energy Technology Data Exchange (ETDEWEB)

    Boye, Pit

    2010-02-05

    This thesis is concerned with the optimization and development of the production of nanofocusing refractive X-ray lenses. These optics made of either silicon or diamond are well-suited for high resolution X-ray microscopy. The goal of this work is the design of a reproducible manufacturing process which allows the production of silicon lenses with high precision, high quality and high piece number. Furthermore a process for the production of diamond lenses is to be developed and established. In this work, the theoretical basics of X-rays and their interaction with matter are described. Especially, aspects of synchrotron radiation are emphasized. Important in X-ray microscopy are the different optics. The details, advantages and disadvantages, in particular those of refractive lenses are given. To achieve small X-ray beams well beyond the 100 nm range a small focal length is required. This is achieved in refractive lenses by moving to a compact lens design where several single lenses are stacked behind each other. The, so-called nanofocusing refractive lenses (NFLs) have a parabolic cylindrical shape with lateral structure sizes in the micrometer range. NFLs are produced by using micro-machining techniques. These micro-fabrication processes and technologies are introduced. The results of the optimization and the final fabrication process for silicon lenses are presented. Subsequently, two experiments that are exemplary for the use of NFLs, are introduced. The rst one employs a high-resolution scanning fluorescence mapping of a geological sample, and the second one is a coherent x-ray diffraction imaging (CXDI) experiment. CXDI is able to reconstruct the illuminated object from recorded coherent diffraction patterns. In a scanning mode, referred to as ptychography, this method is even able to reconstruct the illumination and the object simultaneously. Especially the reconstructed illumination and the possibility of computed propagation of the wave field along the

  4. Stellar X-Ray Polarimetry

    Science.gov (United States)

    Swank, J.

    2011-01-01

    Most of the stellar end-state black holes, pulsars, and white dwarfs that are X-ray sources should have polarized X-ray fluxes. The degree will depend on the relative contributions of the unresolved structures. Fluxes from accretion disks and accretion disk corona may be polarized by scattering. Beams and jets may have contributions of polarized emission in strong magnetic fields. The Gravity and Extreme Magnetism Small Explorer (GEMS) will study the effects on polarization of strong gravity of black holes and strong magnetism of neutron stars. Some part of the flux from compact stars accreting from companion stars has been reflected from the companion, its wind, or accretion streams. Polarization of this component is a potential tool for studying the structure of the gas in these binary systems. Polarization due to scattering can also be present in X-ray emission from white dwarf binaries and binary normal stars such as RS CVn stars and colliding wind sources like Eta Car. Normal late type stars may have polarized flux from coronal flares. But X-ray polarization sensitivity is not at the level needed for single early type stars.

  5. X-Ray Diffractive Optics

    Science.gov (United States)

    Dennis, Brian; Li, Mary; Skinner, Gerald

    2013-01-01

    X-ray optics were fabricated with the capability of imaging solar x-ray sources with better than 0.1 arcsecond angular resolution, over an order of magnitude finer than is currently possible. Such images would provide a new window into the little-understood energy release and particle acceleration regions in solar flares. They constitute one of the most promising ways to probe these regions in the solar atmosphere with the sensitivity and angular resolution needed to better understand the physical processes involved. A circular slit structure with widths as fine as 0.85 micron etched in a silicon wafer 8 microns thick forms a phase zone plate version of a Fresnel lens capable of focusing approx. =.6 keV x-rays. The focal length of the 3-cm diameter lenses is 100 microns, and the angular resolution capability is better than 0.1 arcsecond. Such phase zone plates were fabricated in Goddard fs Detector Development Lab. (DDL) and tested at the Goddard 600-microns x-ray test facility. The test data verified that the desired angular resolution and throughput efficiency were achieved.

  6. X-rays and magnetism.

    Science.gov (United States)

    Fischer, Peter; Ohldag, Hendrik

    2015-09-01

    Magnetism is among the most active and attractive areas in modern solid state physics because of intriguing phenomena interesting to fundamental research and a manifold of technological applications. State-of-the-art synthesis of advanced magnetic materials, e.g. in hybrid structures paves the way to new functionalities. To characterize modern magnetic materials and the associated magnetic phenomena, polarized x-rays have emerged as unique probes due to their specific interaction with magnetic materials. A large variety of spectroscopic and microscopic techniques have been developed to quantify in an element, valence and site-sensitive way properties of ferro-, ferri-, and antiferromagnetic systems, such as spin and orbital moments, and to image nanoscale spin textures and their dynamics with sub-ns time and almost 10 nm spatial resolution. The enormous intensity of x-rays and their degree of coherence at next generation x-ray facilities will open the fsec time window to magnetic studies addressing fundamental time scales in magnetism with nanometer spatial resolution. This review will give an introduction into contemporary topics of nanoscale magnetic materials and provide an overview of analytical spectroscopy and microscopy tools based on x-ray dichroism effects. Selected examples of current research will demonstrate the potential and future directions of these techniques.

  7. X-ray backscatter imaging

    Science.gov (United States)

    Dinca, Dan-Cristian; Schubert, Jeffrey R.; Callerame, J.

    2008-04-01

    In contrast to transmission X-ray imaging systems where inspected objects must pass between source and detector, Compton backscatter imaging allows both the illuminating source as well as the X-ray detector to be on the same side of the target object, enabling the inspection to occur rapidly and in a wide variety of space-constrained situations. A Compton backscatter image is similar to a photograph of the contents of a closed container, taken through the container walls, and highlights low atomic number materials such as explosives, drugs, and alcohol, which appear as especially bright objects by virtue of their scattering characteristics. Techniques for producing X-ray images based on Compton scattering will be discussed, along with examples of how these systems are used for both novel security applications and for the detection of contraband materials at ports and borders. Differences between transmission and backscatter images will also be highlighted. In addition, tradeoffs between Compton backscatter image quality and scan speed, effective penetration, and X-ray source specifications will be discussed.

  8. Alpha proton x ray spectrometer

    Science.gov (United States)

    Rieder, Rudi; Waeke, H.; Economou, T.

    1994-01-01

    Mars Pathfinder will carry an alpha-proton x ray spectrometer (APX) for the determination of the elemental chemical composition of Martian rocks and soils. The instrument will measure the concentration of all major and some minor elements, including C, N, and O at levels above typically 1 percent.

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... for more information about pregnancy and x-rays. A Word About Minimizing Radiation Exposure Special care is ... encourage linking to this site. × Recommend RadiologyInfo to a friend Send to (friend's e-mail address): From ( ...

  10. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...

  11. Digital chest radiography

    DEFF Research Database (Denmark)

    Debess, Jeanne Elisabeth; Johnsen, Karen Kirstine; Thomsen, Henrik

    2015-01-01

    on collimation and dose reduction in digital chest radiography Methods and Materials A retrospective study of digital chest radiography is performed to evaluate the primary x-ray tube collimation of the PA and lateral radiographs. Data from one hundred fifty self-reliant female patients between 15 and 55 years...... collimations depending on side of radiograph. Results from dose reduction will be presented on the congress Conclusion: Correct positioning and collimation of digital chest radiographs can reduce the radiation dose significant to the patients and by that improve the quality of basic radiography....

  12. High-Resolution X-ray Emission and X-ray Absorption Spectroscopy

    OpenAIRE

    de Groot, F. M. F.

    2001-01-01

    In this review, high-resolution X-ray emission and X-ray absorption spectroscopy will be discussed. The focus is on the 3d transition-metal systems. To understand high-resolution X-ray emission and reso-nant X-ray emission, it is first necessary to spend some time discussing the X-ray absorption process. Section II discusses 1s X-ray absorption, i.e., the K edges, and section III deals with 2p X-ray absorption, the L edges. X-ray emission is discussed in, respectively, the L edges. X-ray emis...

  13. Correlation length of X-ray brightest Abell clusters

    CERN Document Server

    Abadi, M G; Muriel, H; Abadi, Mario G; Lambas, Diego G.; Muriel, Hernán

    1998-01-01

    We compute the cluster auto-correlation function $\\xi_{cc}(r)$ of an X-ray flux limited sample of Abell clusters (XBACs, \\cite{ebe}). For the total XBACs sample we find a power-law fit $\\xi_{cc}=(r/r_0)^{\\gamma}$ with $r_0=21.1$ Mpc h$^{-1}$and $\\gamma =-1.9$ consistent with the results of $R \\ge 1 $ Abell clusters. We also analyze $\\xi_{cc}(r)$ for subsamples defined by different X-ray luminosity thresholds where we find a weak tendency of larger values of $r_0$ with increasing X-ray luminosity although with a low statistical significance. In the different subsamples analyzed we find $21 < r_0 < 35 $ Mpc h$^{-1}$ and $-1.9< \\gamma < -1.6$. Our analysis suggests that cluster X-ray luminosities may be used for a reliable confrontation of cluster spatial distribution properties in models and observations.

  14. 颈椎生理曲度改变的X线表现及其临床价值%The Value and X-ray Imaging Findings at Physiological Curvature Changeing of Cervical Vertebra

    Institute of Scientific and Technical Information of China (English)

    张建军; 周鹏; 高雪梅; 钟辉

    2008-01-01

    Objective To discuss the value and imaging findings of physiological curvature changeing of cervical vertebra.Methods The x-ray film of imaging representations of 65 cases with physiological curvature changeing of cervical vertebra were retrospectively analysed.Survey chord distance with flank position of cervical vertebra.Results Among 65 patients,43 cases physiological curvature slight changes straight of cervical vertebra,6 cases physiological curvature remarkable changes straight or vanishing or negative of cervical vertebra.Conclusion The value and imaging findings of physiological curvature changeing of cervical vertebra for diagnosis of cervieal vertebra disease.%目的 探讨颈椎生理曲度改变的x线影像学表现及其临床价值.方法 回顾分析65例颈椎生理曲度异常的颈椎X线平片,在颈椎侧位片上测量椎体前缘序列弧线的弧弦距.结果 65例中,颈椎生理曲度轻度变直,其颈椎弧弦距0,或为负值,占9.23%(6/65).结论 颈椎生理曲度改变的X线影像学表现,对颈椎病的诊断有一定的参考价值.

  15. The Million Optical - Radio/X-ray Associations (MORX) Catalogue

    CERN Document Server

    Flesch, Eric W

    2016-01-01

    This automated catalogue combines all the largest published optical, radio and X-ray sky catalogues to find probable radio/X-ray associations to optical objects, plus double radio lobes, using uniform processing against all input data. The total count is 1002855 optical objects so presented. Each object is displayed with J2000 astrometry, optical and radio/X-ray identifiers, red and blue photometry, and calculated probabilities and optical field solutions of the associations. This is the third and final edition of this method.

  16. AGN variability at hard X-rays

    CERN Document Server

    Soldi, S; Beckmann, V; Lubinski, P

    2010-01-01

    We present preliminary results on the variability properties of AGN above 20 keV in order to show the potential of the INTEGRAL IBIS/ISGRI and Swift/BAT instruments for hard X-ray timing analysis of AGN. The 15-50 keV light curves of 36 AGN observed by BAT during 5 years show significantly larger variations when the blazar population is considered (average normalized excess variance = 0.25) with respect to the Seyfert one (average normalized excess variance = 0.09). The hard X-ray luminosity is found to be anti-correlated to the variability amplitude in Seyfert galaxies and correlated to the black hole mass, confirming previous findings obtained with different AGN hard X-ray samples. We also present results on the Seyfert 1 galaxy IC 4329A, as an example of spectral variability study with INTEGRAL/ISGRI data. The position of the high-energy cut-off of this source is found to have varied during the INTEGRAL observations, pointing to a change of temperature of the Comptonising medium. For several bright Seyfert...

  17. Soft-x-ray spectroscopy study of nanoscale materials

    Energy Technology Data Exchange (ETDEWEB)

    Guo, J.-H.

    2005-07-30

    The ability to control the particle size and morphology of nanoparticles is of crucial importance nowadays both from a fundamental and industrial point of view considering the tremendous amount of high-tech applications. Controlling the crystallographic structure and the arrangement of atoms along the surface of nanostructured material will determine most of its physical properties. In general, electronic structure ultimately determines the properties of matter. Soft X-ray spectroscopy has some basic features that are important to consider. X-ray is originating from an electronic transition between a localized core state and a valence state. As a core state is involved, elemental selectivity is obtained because the core levels of different elements are well separated in energy, meaning that the involvement of the inner level makes this probe localized to one specific atomic site around which the electronic structure is reflected as a partial density-of-states contribution. The participation of valence electrons gives the method chemical state sensitivity and further, the dipole nature of the transitions gives particular symmetry information. The new generation synchrotron radiation sources producing intensive tunable monochromatized soft X-ray beams have opened up new possibilities for soft X-ray spectroscopy. The introduction of selectively excited soft X-ray emission has opened a new field of study by disclosing many new possibilities of soft X-ray resonant inelastic scattering. In this paper, some recent findings regarding soft X-ray absorption and emission studies of various nanostructured systems are presented.

  18. Testing for X-ray-SZ Differences and Redshift Evolution in the X-ray Morphology of Galaxy Clusters

    CERN Document Server

    Nurgaliev, D; Benson, B A; Bleem, L; Bocquet, S; Forman, W R; Garmire, G P; Gupta, N; Hlavacek-Larrondo, J; Mohr, J J; Nagai, D; Rapetti, D; Stark, A A; Stubbs, C W; Vikhlinin, A

    2016-01-01

    We present a quantitative study of the X-ray morphology of galaxy clusters, as a function of their detection method and redshift. We analyze two separate samples of galaxy clusters: a sample of 36 clusters at 0.35 < z < 0.9 selected in the X-ray with the ROSAT PSPC 400 deg2 survey, and a sample of 90 clusters at 0.25 < z < 1.2 selected via the Sunyaev-Zel'dovich (SZ) effect with the South Pole Telescope. Clusters from both samples have similar-quality Chandra observations, which allow us to quantify their X-ray morphologies via two distinct methods: centroid shifts and photon asymmetry. The latter technique provides nearly unbiased morphology estimates for clusters spanning a broad range of redshift and data quality. We further compare the X-ray morphologies of X-ray- and SZ-selected clusters with those of simulated clusters. We do not find a statistically significant difference in the measured X-ray morphology of X-ray and SZ-selected clusters over the redshift range probed by these samples, sugg...

  19. First Search for an X-ray -- Optical Reverberation Signal in an Ultraluminous X-ray Source

    CERN Document Server

    Pasham, Dheeraj R; Cenko, S Bradley; Trippe, Margaret L; Mushotzky, Richard F; Gandhi, Poshak

    2016-01-01

    Using simultaneous optical (VLT/FORS2) and X-ray (XMM-Newton) data of NGC 5408, we present the first ever attempt to search for a reverberation signal in an ultraluminous X-ray source (NGC 5408 X-1). The idea is similar to AGN broad line reverberation mapping where a lag measurement between the X-ray and the optical flux combined with a Keplerian velocity estimate should enable us to weigh the central compact object. We find that although NGC 5408 X-1's X-rays are variable on a timescale of a few hundred seconds (RMS of 9.0$\\pm$0.5%), the optical emission does not show any statistically significant variations. We set a 3$\\sigma$ upper limit on the RMS optical variability of 3.3%. The ratio of the X-ray to the optical variability is an indicator of X-ray reprocessing efficiency. In X-ray binaries, this ratio is roughly 5. Assuming a similar ratio for NGC 5408 X-1, the expected RMS optical variability is $\\approx$2% which is still a factor of roughly two lower than what was possible with the VLT observations in...

  20. X-Ray-powered Macronovae

    Science.gov (United States)

    Kisaka, Shota; Ioka, Kunihito; Nakar, Ehud

    2016-02-01

    A macronova (or kilonova) was observed as an infrared excess several days after the short gamma-ray burst GRB 130603B. Although the r-process radioactivity is widely discussed as an energy source, it requires a huge mass of ejecta from a neutron star (NS) binary merger. We propose a new model in which the X-ray excess gives rise to the simultaneously observed infrared excess via thermal re-emission, and explore what constraints this would place on the mass and velocity of the ejecta. This X-ray-powered model explains both the X-ray and infrared excesses with a single energy source such as the central engine like a black hole, and allows for a broader parameter region than the previous models, in particular a smaller ejecta mass ˜ {10}-3{--}{10}-2{M}⊙ and higher iron abundance mixed as suggested by general relativistic simulations for typical NS-NS mergers. We also discuss the other macronova candidates in GRB 060614 and GRB 080503, and the implications for the search of electromagnetic counterparts to gravitational waves.

  1. X-Ray Crystallography Reagent

    Science.gov (United States)

    Morrison, Dennis R. (Inventor); Mosier, Benjamin (Inventor)

    2003-01-01

    Microcapsules prepared by encapsulating an aqueous solution of a protein, drug or other bioactive substance inside a semi-permeable membrane by are disclosed. The microcapsules are formed by interfacial coacervation under conditions where the shear forces are limited to 0-100 dynes per square centimeter at the interface. By placing the microcapsules in a high osmotic dewatering solution. the protein solution is gradually made saturated and then supersaturated. and the controlled nucleation and crystallization of the protein is achieved. The crystal-filled microcapsules prepared by this method can be conveniently harvested and stored while keeping the encapsulated crystals in essentially pristine condition due to the rugged. protective membrane. Because the membrane components themselves are x-ray transparent, large crystal-containing microcapsules can be individually selected, mounted in x-ray capillary tubes and subjected to high energy x-ray diffraction studies to determine the 3-D smucture of the protein molecules. Certain embodiments of the microcapsules of the invention have composite polymeric outer membranes which are somewhat elastic, water insoluble, permeable only to water, salts, and low molecular weight molecules and are structurally stable in fluid shear forces typically encountered in the human vascular system.

  2. Be/X-ray binaries

    CERN Document Server

    Reig, Pablo

    2011-01-01

    The purpose of this work is to review the observational properties of Be/X-ray binaries. The open questions in Be/X-ray binaries include those related to the Be star companion, that is, the so-called "Be phenomenon", such as, timescales associated to the formation and dissipation of the equatorial disc, mass-ejection mechanisms, V/R variability, and rotation rates; those related to the neutron star, such as, mass determination, accretion physics, and spin period evolution; but also, those that result from the interaction of the two constituents, such as, disc truncation and mass transfer. Until recently, it was thought that the Be stars' disc was not significantly affected by the neutron star. In this review, I present the observational evidence accumulated in recent years on the interaction between the circumstellar disc and the compact companion. The most obvious effect is the tidal truncation of the disc. As a result, the equatorial discs in Be/X-ray binaries are smaller and denser than those around isolat...

  3. X-ray bright groups and their galaxies

    CERN Document Server

    Helsdon, S F; Helsdon, Stephen F.; Ponman, Trevor J.

    2002-01-01

    Combining X-ray data from the ROSAT PSPC and optical data drawn from the literature, we examine in detail the relationship between the X-ray and optical properties of X-ray bright galaxy groups. We find a relationship between optical luminosity and X-ray temperature consistent with that expected from self-similar scaling of galaxy systems, L_B \\propto T^{1.6 +/- 0.2}. The self-similar form and continuity of the L_B : T relation from clusters to groups and the limited scatter seen in this relation, implies that the star formation efficiency is rather similar in all these systems. We find that the bright extended X-ray components associated with many central galaxies in groups appear to be more closely related to the group than the galaxy itself, and we suggest that these are group cooling flows rather than galaxy halos. In addition we find that the optical light in these groups appears to be more centrally concentrated than the light in clusters. We also use the optical and X-ray data to investigate whether ea...

  4. Chest radiographic staging in allergic bronchopulmonary aspergillosis: relationship with immunological findings.

    LENUS (Irish Health Repository)

    Kiely, J L

    2012-02-03

    The question of whether a chest radiographic severity staging system could be correlated with standard blood\\/serum diagnostic indices in allergic bronchopulmonary aspergillosis (ABPA) was addressed in 41 patients. Asthma and positive Aspergillus fumigatus (AF) serology were considered essential diagnostic inclusion criteria. Eosinophil count, serum immunoglobulin (Ig)E and immediate skin hypersensitivity were also tested to grade patients as "definite" or "likely" ABPA. Definite cases had all five of these factors present, whereas likely cases had three or more. Chest radiographs were examined by experienced radiologists blinded to the clinical data. The six-stage radiographic score (0-5) was based on the severity and duration of changes seen: stage 0: normal; stage 1: transient hyperinflation; stage 2: transient minor changes; stage 3: transient major changes; stage 4: permanent minor changes; and stage 5: permanent major changes. Significant positive correlations (p<0.05) were observed between peak AF titres (expressed as an index), peak eosinophil count and radiographic severity stage. When considered as subgroups, these correlations approached, but did not reach, significance for the group with "likely" ABPA (n=28), but in the group with definite ABPA (n=13), there was a high correlation between radiographic score and peak AF index (r=0.59), as well as peak eosinophil count (r=0.62). This study suggests that the peak Aspergillus fumigatus index and eosinophil counts correlate best with the severity of radiographic stages in allergic bronchopulmonary aspergillosis. This chest radiographic staging system may be useful in the clinical assessment and management of patients with allergic bronchopulmonary aspergillosis, particularly in those patients with more severe radiographic stages.

  5. 软骨母细胞瘤MRI及X线平片和CT的表现特征%The MRI features of chondroblastoma with correlation of X-ray and CT findings

    Institute of Scientific and Technical Information of China (English)

    上官景俊; 刘吉华; 韩娟娟; 邢成颜

    2008-01-01

    目的 研究软骨母细胞瘤的影像表现,探讨其MRI与X线平片、CT征象的对应关系.方法 分析16例经手术、病理证实的良性软骨母细胞瘤的影像资料,总结其MRI表现与X线平片、CT征象的对应关系.结果 16例软骨母细胞瘤均位于骨骺,大小为0.9 cm×0.8 cm×1.0 cm~4.8 cm×4.3 cm×5.1 cm,呈不同程度的分叶状.在T1WI上以等、低信号为主,T2WI上呈混杂信号,CT上为软组织密度,内见钙化和更低密度区.边缘呈长T1、短T2信号,在CT上表现为硬化边.MRI可见病灶周围有骨髓水肿,在X线和CT上表现为骨质硬化区.病灶邻近软组织肿胀.MRI显示骨膜异常9例,8例与病灶不相邻;X线和(或)CT显示骨膜新生骨6例.MRI显示关节积液12例,CT显示6例.MRI上病灶均呈不均匀强化,骨髓水肿、骨膜反应和软组织肿胀均见强化.软骨母细胞瘤在扩散加权成像(DWI)上呈等、高信号,在MR平扫中的等T1、等T2成分和长T1、长T2成分,以及骨髓水肿、骨膜反应和软组织肿胀在DWI上均呈高信号.结论 MRI和X线平片、CT从不同方面反映软骨母细胞瘤的病理改变,联合应用不同检查手段可更全面显示软骨母细胞瘤的特点.%Objective To investigate the MR imaging features of chondroblastoma,and to address the correlation with findings of X-ray radiography and CT.Methods The imaging findings including MRI,X-ray radiography and CT of 16 chondroblastomas proved by surgery and pathology were analyzed and correlated with each other. Results All sixteen chondroblastomas involved the epiphyses of long bones,with varying sizes from 0.8 cm to 5.1 cm and lobulation. They were iso- and hypo-intense on T1WI and had heterogeneous signals on T2WI.They were of soft tissue density on CT,and had areas of calcifications and low density.The rims were hypointense on both T1 WI and T2 WI and showed hyperdensity on CT. The lesions were surrounded by edema of bone marrow which was hypointense on T1 WI

  6. 乳腺癌钼靶X线表现与分子生物学表达的相关性研究%Breast cancer mammography X-ray findings with the expression of molecular biology research

    Institute of Scientific and Technical Information of China (English)

    安丽华; 陈东风; 李静; 时克伟; 赵小春

    2013-01-01

    Objective Biology explore breast cancer mammography X-ray findings with the cancer cells of the estrogen receptor(ER) and progesterone receptor(PR) and human tumor suppressor gene(P53), aimed at early diagnosis and prognosis of breast provide the basis. Methods A retrospective analysis of 152 patients with pathologically proved infiltrating ductal breast cancer study. The patients preoperative mammography X-ray examination focus observed increased lesion mass, calcification, structural disorder, local density. To histopathological results do control. Postoperative specimens Determination ER, PR, P53 expression analysis of the relationship between them with X-ray mammography performance. Results 152 cases of invasive ductal carcinoma, showed a mass with irregular burrs or form associated with the expression of ER, PR(χ2=8.108, P<0.05; χ2=5.571, P<0.05); Calcification significant difference in expression of ER, PR(χ2=4.851, P<0.05; χ2=4.579, P<0.05); Increased breast structural disorder or local density and ER, PR expression difference was statistically significant(χ2=6.521, P<0.05; χ2=5.602, P<0.05). Breast structural disorder or increased local density and P53 expression significant difference(χ2=7.883, P<0.05). Conclusion Breast cancer mammography X-ray findings exists a certain correlation between ER, PR, P53, to some extent, reflect the biological behavior and prognosis of breast cancer cells, to provide more for the early diagnosis and treatment objective basis.%  目的探讨乳腺癌钼靶X线表现与癌细胞雌激素受体(ER)、孕激素受体(PR)及人体抑癌基因(P53)生物学相关性,旨在为乳腺癌的早期诊断及预测预后提供依据.方法回顾性分析经手术病理证实的152例乳腺浸润性导管癌患者为研究对象.患者均于术前行钼靶X线检查,重点观察病变肿块、钙化、结构紊乱、局部密度增高等.以病理组织学结果做对照.术后标本测定ER、PR、P53

  7. Congenital left ventricular diverticulum, a rare chest fluoroscopy finding: a case report

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-wei; WU Hong-bing; MAO Zhi-fu; HU Xiao-ping

    2011-01-01

    Congenital left ventricular diverticulum is a very rare cardiac abnormality and it is not completely understood about its etiology, clinical manifestation, diagnosis, treatment and prognosis. This article presents a case of large congenital diverticulum of the left ventricle. The clinical manifestation included paroxysmal supraventricular tachycardia. The diagnosis was made by chest fluoroscopy observation and confirmed by 64-slice CT-angiography. The arrhythmia alleviated instead of antiarrhythmic drugs but by radiofrequency catheter ablation. Due to the rapid growth of the diverticulum, the patient underwent surgical resection finally. Owing to the fatal risks, clinicians should improve the understanding of this disease by deeply studying more cases, in order to standardize the treatment.

  8. Chest Radiographic Findings of Novel Swine-Origin Influenza A (H1N1) Virus Infection in Children

    Energy Technology Data Exchange (ETDEWEB)

    Bae, So Young; Hong, Eun Sook; Paik, Sang Hyun; Park, Seong Jin; Cha, Jang Gyu; Lee, Hae Kyung [Dept. of Radiology, Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of); Jang, Yun Woo [Dept. of Radiology, Soonchunhyang University Hospital, Seoul (Korea, Republic of)

    2011-06-15

    To analyze chest radiographic findings in children infected with laboratory confirmed novel swine-origin influenza A (H1N1) virus. Three hundred seventy-two out of 2,014 children with laboratory confirmed H1N1 infection and who also underwent a chest radiograph from September to November 2009 were enrolled in this study. Patients were divided into in-patients, out-patients, and patients with co-infections and further subdivided into with underlying disease and without underlying disease as well as age (<2 years old, 2-5 years, 5-10 years, 10-18 years old). The initial radiographs were evaluated for radiographic findings and the anatomic distribution of abnormalities. The initial radiographs were abnormal in 154 (41.39%) patients. The predominant radiographic findings were peribronchial wall opacity found in 85 (22.84%) patients and hyperinflation observed in 69 (18.54%) patients. Further, 75 (71.42%) patients exhibited central predominance and the right lower lung zone was also commonly involved. There were statistically significant differences in the radiological findings between in-patient and out-patient groups. However, there were no significant differences in the radiographic findings between in-patients and the co-infection group with respect the presence of underlying disease and age. Initial radiographs of children with laboratory confirmed H1N1 virus were abnormal in 41.39% of cases. The common radiographic findings included peribronchial opacities, hyperinflation, lower lung zonal distribution, and central predominance

  9. X-ray optics for axion helioscopes

    DEFF Research Database (Denmark)

    Jakobsen, Anders Clemen; Pivovaroff, Michael J.; Christensen, Finn Erland

    2013-01-01

    A method of optimizing grazing incidence x-ray coatings in ground based axion helioscopes is presented. Software has been been developed to find the optimum coating when taking both axion spectrum and Micromegas detector quantum efficiency into account. A comparison of the relative effective area...... in the telescope using different multilayer material combinations is produced. Similar methods are used for IAXO, a planned axion helioscope. Additionally, the optimal focal length is modelled while taking into account the least possible background contribution from the detector. © (2013) COPYRIGHT Society...

  10. Cryotomography x-ray microscopy state

    Science.gov (United States)

    Le Gros, Mark; Larabell, Carolyn A.

    2010-10-26

    An x-ray microscope stage enables alignment of a sample about a rotation axis to enable three dimensional tomographic imaging of the sample using an x-ray microscope. A heat exchanger assembly provides cooled gas to a sample during x-ray microscopic imaging.

  11. X-Ray Exam: Scoliosis (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Scoliosis KidsHealth > For Parents > X-Ray Exam: Scoliosis A A A What's in ... español Radiografía: escoliosis What It Is A scoliosis X-ray is a relatively safe and painless test ...

  12. X-Ray Exam: Neck (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Neck KidsHealth > For Parents > X-Ray Exam: Neck A A A What's in ... español Radiografía: cuello What It Is A neck X-ray is a safe and painless test that ...

  13. X-Ray Exam: Femur (Upper Leg)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Femur (Upper Leg) KidsHealth > For Parents > X-Ray Exam: Femur (Upper Leg) A A A ... español Radiografía: fémur What It Is A femur X-ray is a safe and painless test that ...

  14. X-Ray Exam: Cervical Spine

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Cervical Spine KidsHealth > For Parents > X-Ray Exam: Cervical Spine A A A What's ... columna cervical What It Is A cervical spine X-ray is a safe and painless test that ...

  15. Finding on a chest radiograph: A dangerous complication of subclavian vein cannulation

    Directory of Open Access Journals (Sweden)

    Srinivasan Nataraj

    2010-01-01

    Full Text Available Cannulation of the subclavian vein has its inherent risks. Post procedure chest radiograph is one of the investigations done to rule out immediate complications. Unless the clinician is aware as to what to look for in the radiograph, some of the dangerous complications can be overlooked. Accidental subclavian artery cannulation is identified immediately by color and jet of the blood. Also the position of the catheter tip has to be confirmed by obtaining the arterial pressure tracing using a pressure transducer. Non availability of Doppler ultrasound and pressure transducer are limiting factors for immediate confirmation of proper catheter placement. Also, in patients with severe hypotension and reduced oxygen content of blood, accidental arterial puncture may not show the characteristic bright red pulsatile back flow of arterial blood. In these situations radiography can be used as a diagnostic tool to rule out subclavian artery cannulation.

  16. Comets: mechanisms of x-ray activity

    Science.gov (United States)

    Ibadov, Subhon

    2016-07-01

    Basic mechanisms of X-ray activity of comets are considered, including D-D mechanism corresponding to generation of X-rays due to production of hot short-living plasma clumps at high-velocity collisions between cometary and interplanetary dust particles as well as M-M one corresponding to production of X-rays due to recombination of multicharge ions of solar wind plasma via charge exchange process at their collisions with molecules/atoms of the cometary atmospheres. Peculiarities of the variation of the comet X-ray spectrum and X-ray luminosity with variation of its heliocentric distance are revealed.

  17. X-Ray Visions of SS Cygni

    Science.gov (United States)

    Young, D. L.

    2004-12-01

    The Chandra X-Ray Observatory is the most sophisticated X-ray observatory launched by NASA. Chandra is designed to observe X-rays from highenergy regions of the universe, such as X-ray binary stars. On September 14, 2000, triggered by alerts from amateur astronomers worldwide, Chandra observed the outburst of the brightest northern dwarf nova SS Cygni. The cooperation of hundreds of amateur variable star astronomers and the Chandra X-Ray scientists and spacecraft specialists provided proof that the collaboration of amateur and professional astronomers is a powerful tool to study cosmic phenomena.

  18. Chest radiographic manifestations of scrub typhus

    Directory of Open Access Journals (Sweden)

    KPP Abhilash

    2016-01-01

    Full Text Available Background and Rationale: Respiratory system involvement in scrub typhus is seen in 20–72% of patients. In endemic areas, good understanding and familiarity with the various radiologic findings of scrub typhus are essential in identifying pulmonary complications. Materials and Methods: Patients admitted to a tertiary care center with scrub typhus between October 2012 and September 2013 and had a chest X ray done were included in the analysis. Details and radiographic findings were noted and factors associated with abnormal X-rays were analyzed. Results: The study cohort contained 398 patients. Common presenting complaints included fever (100%, generalized myalgia (83%, headache (65%, dyspnea (54%, cough (24.3%, and altered sensorium (14%. Almost half of the patients (49.4% had normal chest radiographs. Common radiological pulmonary abnormalities included pleural effusion (14.6%, acute respiratory distress syndrome (14%, airspace opacity (10.5%, reticulonodular opacities (10.3%, peribronchial thickening (5.8%, and pulmonary edema (2%. Cardiomegaly was noted in 3.5% of patients. Breathlessness, presence of an eschar, platelet counts of 2 mg/dL had the highest odds of having an abnormal chest radiograph. Patients with an abnormal chest X-ray had a higher requirement of noninvasive ventilation (odds ratio [OR]: 13.98; 95% confidence interval CI: 5.89–33.16, invasive ventilation (OR: 18.07; 95% CI: 6.42–50.88, inotropes (OR: 8.76; 95% CI: 4.35–17.62, higher involvement of other organ systems, longer duration of hospital stay (3.18 ± 3 vs. 7.27 ± 5.58 days; P< 0.001, and higher mortality (OR: 4.63; 95% CI: 1.54–13.85. Conclusion: Almost half of the patients with scrub typhus have abnormal chest radiographs. Chest radiography should be included as part of basic evaluation at presentation in patients with scrub typhus, especially in those with breathlessness, eschar, jaundice, and severe thrombocytopenia.

  19. Extended X-ray emission from radio galaxy cocoons

    CERN Document Server

    Nath, Biman B

    2010-01-01

    We study the emission of X-rays from lobes of FR-II radio galaxies by inverse Compton scattering of microwave background photons. Using a simple model that takes into account injection of relativistic electrons, their energy losses through adiabatic expansion, synchrotron and inverse Compton emission, and also the stopping of the jet after a certain time, we study the evolution of the total X-ray power, the surface brightness, angular size of the X-ray bright region and the X-ray photon index, as functions of time and cocoon size, and compare the predictions with observations. We find that the radio power drops rapidly after the stopping of the jet, with a shorter time-scale than the X-ray power. The X-ray spectrum initially hardens until the jet stops because the steepening of electron spectrum is mitigated by the injection of fresh particles, for electrons with $\\gamma \\ge 10^3$. This happens because of the concurrence of two times scales, that of the typical jet lifetimes and cooling due to inverse Compton...

  20. A Catalog of Intermediate-luminosity X-ray Objects

    CERN Document Server

    Colbert, E

    2002-01-01

    ROSAT, and now Chandra, X-ray images allow studies of extranuclear X-ray point sources in galaxies other than our own. X-ray observations of normal galaxies with ROSAT and Chandra have revealed that off-nuclear, compact, Intermediate-luminosity (Lx 2-10 keV >= 1e39 erg/s) X-ray Objects (IXOs, a.k.a. ULXs) are quite common. Here we present a catalog and finding charts for 87 IXOs in 54 galaxies, derived from all of the ROSAT HRI imaging data for galaxies with cz <= 5000 km/s from the Third Reference Catalog of Bright Galaxies (RC3). We have defined the cutoff Lx for IXOs so that it is well above the Eddington luminosity of a 1.4 Msol black hole (10^{38.3} erg/s), so as not to confuse IXOs with ``normal'' black hole X-ray binaries. This catalog is intended to provide a baseline for follow-up work with Chandra, and with space- and ground-based survey work at wavelengths other than X-ray. We demonstrate that elliptical galaxies with IXOs have a larger number of IXOs per galaxy than non-elliptical galaxies with...

  1. X-ray pulse wavefront metrology using speckle tracking.

    Science.gov (United States)

    Berujon, Sebastien; Ziegler, Eric; Cloetens, Peter

    2015-07-01

    An instrument allowing the quantitative analysis of X-ray pulsed wavefronts is presented and its processing method explained. The system relies on the X-ray speckle tracking principle to accurately measure the phase gradient of the X-ray beam from which beam optical aberrations can be deduced. The key component of this instrument, a semi-transparent scintillator emitting visible light while transmitting X-rays, allows simultaneous recording of two speckle images at two different propagation distances from the X-ray source. The speckle tracking procedure for a reference-less metrology mode is described with a detailed account on the advanced processing schemes used. A method to characterize and compensate for the imaging detector distortion, whose principle is also based on speckle, is included. The presented instrument is expected to find interest at synchrotrons and at the new X-ray free-electron laser sources under development worldwide where successful exploitation of beams relies on the availability of an accurate wavefront metrology.

  2. On the X-ray heated skin of Accretion Disks

    CERN Document Server

    Nayakshin, S

    1999-01-01

    We present a simple analytical formula for the Thomson depth of the X-rayheated skin of accretion disks valid at any radius and for a broad range ofspectral indices of the incident X-rays, accretion rates and black hole masses.We expect that this formula may find useful applications in studies of geometryof the inner part of accretion flows around compact objects, and in severalother astrophysically important problems, such as the recently observed X-ray``Baldwin'' effect (i.e., monotonic decrease of Fe line's equivalent width withthe X-ray luminosity of AGN), the problem of missing Lyman edge in AGN, andline and continuum variability studies in accretion disks around compactobjects. We compute the reflected X-ray spectra for several representativecases and show that for hard X-ray spectra and large ionizing fluxes the skinrepresents a perfect mirror that does not produce any Fe lines or absorptionfeatures. At the same time, for soft X-ray spectra or small ionizing fluxes,the skin produces very strong ionized...

  3. A short working distance multiple crystal x-ray spectrometer

    Science.gov (United States)

    Dickinson, B.; Seidler, G.T.; Webb, Z.W.; Bradley, J.A.; Nagle, K.P.; Heald, S.M.; Gordon, R.A.; Chou, I.-Ming

    2008-01-01

    For x-ray spot sizes of a few tens of microns or smaller, a millimeter-sized flat analyzer crystal placed ???1 cm from the sample will exhibit high energy resolution while subtending a collection solid angle comparable to that of a typical spherically bent crystal analyzer (SBCA) at much larger working distances. Based on this observation and a nonfocusing geometry for the analyzer optic, we have constructed and tested a short working distance (SWD) multicrystal x-ray spectrometer. This prototype instrument has a maximum effective collection solid angle of 0.14 sr, comparable to that of 17 SBCA at 1 m working distance. We find good agreement with prior work for measurements of the Mn K?? x-ray emission and resonant inelastic x-ray scattering for MnO, and also for measurements of the x-ray absorption near-edge structure for Dy metal using L??2 partial-fluorescence yield detection. We discuss future applications at third- and fourth-generation light sources. For concentrated samples, the extremely large collection angle of SWD spectrometers will permit collection of high-resolution x-ray emission spectra with a single pulse of the Linac Coherent Light Source. The range of applications of SWD spectrometers and traditional multi-SBCA instruments has some overlap, but also is significantly complementary. ?? 2008 American Institute of Physics.

  4. The recent development of an X-ray grating interferometer at Shanghai Synchrotron Radiation Facility

    Energy Technology Data Exchange (ETDEWEB)

    Sun Haohua; Kou Bingquan; Xi Yan; Qi Juncheng; Sun Jianqi; Mohr, Juergen; Boerner, Martin; Zhao Jun; Xu, Lisa X.; Xiao Tiqiao; Wang Yujie [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China) and Med-X Research Institute, Shanghai Jiao Tong University, Shanghai 200040 (China); Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Karlsruhe Institute of Technology (KIT), Institute for Microstructure Technology (IMT), Hermannvon-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2012-07-31

    An X-ray grating interferometer has been installed at Shanghai Synchrotron Radiation Facility (SSRF). Three sets of phase gratings were designed to cover the wide X-ray energy range needed for biological and soft material imaging capabilities. The performance of the grating interferometer has been evaluated by a tomography study of a PMMA particle packing and a new born mouse chest. In the mouse chest study, the carotid artery and carotid vein inside the mouse can be identified in situ without contrast agents.

  5. X-rays from solar system objects

    CERN Document Server

    Bhardwaj, Anil; Gladstone, G Randall; Cravens, Thomas E; Lisse, Carey M; Dennerl, Konrad; Branduardi-Raymont, Graziella; Wargelin, Bradford J; Waite, J Hunter; Robertson, Ina; Ostgaard, Nikolai; Beiersdorfer, Peter; Snowden, Steven L; Kharchenko, Vasili; 10.1016/j.pss.2006.11.009

    2010-01-01

    During the last few years our knowledge about the X-ray emission from bodies within the solar system has significantly improved. Several new solar system objects are now known to shine in X-rays at energies below 2 keV. Apart from the Sun, the known X-ray emitters now include planets (Venus, Earth, Mars, Jupiter, and Saturn), planetary satellites (Moon, Io, Europa, and Ganymede), all active comets, the Io plasma torus (IPT), the rings of Saturn, the coronae (exospheres) of Earth and Mars, and the heliosphere. The advent of higher-resolution X-ray spectroscopy with the Chandra and XMM-Newton X-ray observatories has been of great benefit in advancing the field of planetary X-ray astronomy. Progress in modeling X-ray emission, laboratory studies of X-ray production, and theoretical calculations of cross-sections, have all contributed to our understanding of processes that produce X-rays from the solar system bodies. At Jupiter and Earth, both auroral and non-auroral disk X-ray emissions have been observed. X-ray...

  6. Digital chest radiography

    DEFF Research Database (Denmark)

    Debess, Jeanne Elisabeth; Vejle-Sørensen, Jens Kristian; Thomsen, Henrik;

    2015-01-01

    of clinical supervisors. Optimal collimation is determined by European and Regional Danish guidelines. The areal between current and optimal collimation is calculated. The experimental research is performed in September - October 2014 Siemens Axiom Aristos digital radiography system DR using 150 kV, 1,25 -3......Purpose: Quality improvement of basic radiography focusing on collimation and dose reduction in digital chest radiography Methods and Materials:A retrospective study of digital chest radiography is performed to evaluate the primary x-ray tube collimation of the PA and lateral radiographs. Data from...... one hundred fifty self-reliant female patients between 15 and 55 years of age are included in the study. The clinical research is performed between September and November 2014 where 3rd year Radiography students collect data on four Danish x-ray departments using identical procedures under guidance...

  7. Full-field transmission x-ray imaging with confocal polycapillary x-ray optics.

    Science.gov (United States)

    Sun, Tianxi; Macdonald, C A

    2013-02-07

    A transmission x-ray imaging setup based on a confocal combination of a polycapillary focusing x-ray optic followed by a polycapillary collimating x-ray optic was designed and demonstrated to have good resolution, better than the unmagnified pixel size and unlimited by the x-ray tube spot size. This imaging setup has potential application in x-ray imaging for small samples, for example, for histology specimens.

  8. A new method for determining the sensitivity of X-ray imaging observations and the X-ray number counts

    CERN Document Server

    Georgakakis, A; Laird, E S; Aird, J; Trichas, M

    2008-01-01

    We present a new method for determining the sensitivity of X-ray imaging observations, which correctly accounts for the observational biases that affect the probability of detecting a source of a given X-ray flux, without the need to perform a large number of time consuming simulations. We use this new technique to estimate the X-ray source counts in different spectral bands (0.5-2, 0.5-10, 2-10 and 5-10keV) by combining deep pencil-beam and shallow wide-area Chandra observations. The sample has a total of 6295 unique sources over an area of $\\rm 11.8deg^2$ and is the largest used to date to determine the X-ray number counts. We determine, for the first time, the break flux in the 5-10 keV band, in the case of a double power-law source count distribution. We also find an upturn in the 0.5-2keV counts at fluxes below about 6e-17erg/s/cm2. We show that this can be explained by the emergence of normal star-forming galaxies which dominate the X-ray population at faint fluxes. The fraction of the diffuse X-ray bac...

  9. Symptomatic pulmonary lipiodol embolism after transarterial chemoembolization for hepatic malignant tumor: clinical presentation and chest imaging findings

    Institute of Scientific and Technical Information of China (English)

    Xu Haifeng; Yang Renjie; Wang Xiaodong; Zhu Xu; Chen Hui

    2014-01-01

    Background Pulmonary lipiodol embolism after transarterial chemoembolization (TACE) was rare and life-threatening,occasionally reported in previous literatures.We aimed to review the records of 11 patients with pulmonary oily embolism and analyze their characteristics of radiographic findings and risk factors.Methods Records of 478 consecutive patients who underwent 1 026 percutaneous TACE procedures were retrospectively analyzed.Eleven cases with respiratory symptoms were identified as having symptomatic pulmonary lipiodol embolism after TACE.Data of these patients,including clinical presentation,techniques of TACE,imaging features of tumor and chest imaging findings,were assessed.Results Eleven (2.3%) of 478 consecutive patients who underwent percutaneous TACE procedures had a pulmonary oily embolism after procedures.The mean size of target tumors embolized was (13.6±2.0) cm.All were hyper-vascular.The mean volume of lipiodol was (21.8±8.2) ml.Pulmonary oily embolisms were revealed within 12-48 hours after TACE.The most severe respiratory symptoms and imaging abnormalities of the eight patients who survived presented between 2 and 5 days after TACE,becoming normal between 12 and 35 days after TACE.Three patients died.Chest CT revealed retention of radiopaque lipiodol in lungs.Conclusions Pulmonary lipiodol embolism occurs easily in patients who have large hyper-vascular hepatic malignant tumor.The high-density lipiodol deposition in the lung field can be used as diagnostic feature.

  10. X-Ray Attenuation Cell

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D.; Toor, A.

    2000-03-03

    To minimize the pulse-to-pulse variation, the LCLS FEL must operate at saturation, i.e. 10 orders of magnitude brighter spectral brilliance than 3rd-generation light sources. At this intensity, ultra-high vacuums and windowless transport are required. Many of the experiments, however, will need to be conducted at a much lower intensity thereby requiring a reliable means to reduce the x-ray intensity by many orders of magnitude without increasing the pulse-to-pulse variation. In this report we consider a possible solution for controlled attenuation of the LCLS x-ray radiation. We suggest using for this purpose a windowless gas-filled cell with the differential pumping. Although this scheme is easily realizable in principle, it has to be demonstrated that the attenuator can be made short enough to be practical and that the gas loads delivered to the vacuum line of sight (LOS) are acceptable. We are not going to present a final, optimized design. Instead, we will provide a preliminary analysis showing that the whole concept is robust and is worth further study. The spatial structure of the LCLS x-ray pulse at the location of the attenuator is shown in Fig. 1. The central high-intensity component, due to the FEL, has a FWHM of {approx}100 {micro}m. A second component, due to the undulator's broad band spontaneous radiation is seen as a much lower intensity ''halo'' with a FWHM of 1 mm. We discuss two versions of the attenuation cell. The first is directed towards a controlled attenuation of the FEL up to the 4 orders of magnitude in the intensity, with the spontaneous radiation halo being eliminated by collimators. In the second version, the spontaneous radiation is not sacrificed but the FEL component (as well as the first harmonic of the spontaneous radiation) gets attenuated by a more modest factor up to 100. We will make all the estimates assuming that the gas used in the attenuator is Xenon and that the energy of the FEL is 8.25 keV. At

  11. Controlling X-rays With Light

    Energy Technology Data Exchange (ETDEWEB)

    Glover, Ernie; Hertlein, Marcus; Southworth, Steve; Allison, Tom; van Tilborg, Jeroen; Kanter, Elliot; Krassig, B.; Varma, H.; Rude, Bruce; Santra, Robin; Belkacem, Ali; Young, Linda

    2010-08-02

    Ultrafast x-ray science is an exciting frontier that promises the visualization of electronic, atomic and molecular dynamics on atomic time and length scales. A largelyunexplored area of ultrafast x-ray science is the use of light to control how x-rays interact with matter. In order to extend control concepts established for long wavelengthprobes to the x-ray regime, the optical control field must drive a coherent electronic response on a timescale comparable to femtosecond core-hole lifetimes. An intense field is required to achieve this rapid response. Here an intense optical control pulse isobserved to efficiently modulate photoelectric absorption for x-rays and to create an ultrafast transparency window. We demonstrate an application of x-ray transparencyrelevant to ultrafast x-ray sources: an all-photonic temporal cross-correlation measurement of a femtosecond x-ray pulse. The ability to control x-ray/matterinteractions with light will create new opportunities at current and next-generation x-ray light sources.

  12. Diffractive X-Ray Telescopes

    Science.gov (United States)

    Skinner, Gerald K.

    2010-01-01

    Diffractive X-ray telescopes, using zone plates, phase Fresnel lenses, or related optical elements have the potential to provide astronomers with true imaging capability with resolution many orders of magnitude better than available in any other waveband. Lenses that would be relatively easy to fabricate could have an angular resolution of the order of micro-arc-seconds or even better, that would allow, for example, imaging of the distorted spacetime in the immediate vicinity of the super-massive black holes in the center of active galaxies. What then is precluding their immediate adoption? Extremely long focal lengths, very limited bandwidth, and difficulty stabilizing the image are the main problems. The history, and status of the development of such lenses is reviewed here and the prospects for managing the challenges that they present are discussed.

  13. Diffractive X-ray Telescopes

    CERN Document Server

    Skinner, Gerald K

    2010-01-01

    Diffractive X-ray telescopes using zone plates, phase Fresnel lenses, or related optical elements have the potential to provide astronomers with true imaging capability with resolution several orders of magnitude better than available in any other waveband. Lenses that would be relatively easy to fabricate could have an angular resolution of the order of micro-arc-seconds or even better, that would allow, for example, imaging of the distorted space- time in the immediate vicinity of the super-massive black holes in the center of active galaxies What then is precluding their immediate adoption? Extremely long focal lengths, very limited bandwidth, and difficulty stabilizing the image are the main problems. The history, and status of the development of such lenses is reviewed here and the prospects for managing the challenges that they present are discussed.

  14. X-ray image enhancement via determinant based feature selection.

    Science.gov (United States)

    Tappenden, R; Hegarty, J; Broughton, R; Butler, A; Coope, I; Renaud, P

    2013-12-01

    Previous work has investigated the feasibility of using Eigenimage-based enhancement tools to highlight abnormalities on chest X-rays (Butler et al in J Med Imaging Radiat Oncol 52:244-253, 2008). While promising, this approach has been limited by computational restrictions of standard clinical workstations, and uncertainty regarding what constitutes an adequate sample size. This paper suggests an alternative mathematical model to the above referenced singular value decomposition method, which can significantly reduce both the required sample size and the time needed to perform analysis. Using this approach images can be efficiently separated into normal and abnormal parts, with the potential for rapid highlighting of pathology.

  15. Connections between the Radio, Optical and Soft X-ray Luminosities for Flat-Spectrum Radio Quasars

    Indian Academy of Sciences (India)

    Zhi-Fu Chen; Cai-Juan Pan; You-Bing Li; Yu-Tao Zhou

    2014-09-01

    We investigate the connections between radio, optical and soft X-ray luminosities with a sample of 538 FSRQs. We find that the radio luminosity is strongly correlated with the optical luminosity, as well as with the soft X-ray luminosity. We also find that the optical luminosity is strongly correlated with the soft X-ray luminosity.

  16. Potentiality of early chest roentgen examination in ventilator treated newborn infants to predict future lung function and disease

    Energy Technology Data Exchange (ETDEWEB)

    Mortensson, W. (St. Goeran' s Children' s Hospital, Stockholm (Sweden). Dept. of Diagnostic Radiology); Andreasson, B.; Lindroth, M.; Svenningsen, N. (Lund Univ. (Sweden). Dept. of Pediatrics); Jonson, B. (Lund Univ. (Sweden). Dept. of Clinical Physiology)

    1989-11-01

    The potentiality of early chest X-ray to predict the risk of lung function abnormalities was studied prospectively in 40 preterm ventilator treated infants in a 8-10-year follow-up investigation. According to the findings at chest X-ray 3 to 10 days after completed ventilator treatment the infants were divided into 3 groups considered to respresent increasing risk and severity of lung damage: (1) normal findings, (2) interstitial parenchymal abnormalities exclusively or (3) in combination with local or general hyperinflation. Lung function tests and chest X-ray were performed at the age of 8 to 10 years. A correlation was found between the findings at the early chest roentgen examination and the risk of abnormal lung function at the follow-up. Occurrence of focal or general hyperinflation or both were associated with a greater risk of airway obstruction. Infants with only interstitial abnormalities were, however, at a higher risk than those with normal chest examination to develop general hyperinflation and increased air way obstruction. (orig.).

  17. Handbook of X-Ray Data

    CERN Document Server

    Zschornack, Günter

    2007-01-01

    This sourcebook is intended as an X-ray data reference for scientists and engineers working in the field of energy or wavelength dispersive X-ray spectrometry and related fields of basic and applied research, technology, or process and quality controlling. In a concise and informative manner, the most important data connected with the emission of characteristic X-ray lines are tabulated for all elements up to Z = 95 (Americium). This includes X-ray energies, emission rates and widths as well as level characteristics such as binding energies, fluorescence yields, level widths and absorption edges. The tabulated data are characterized and, in most cases, evaluated. Furthermore, all important processes and phenomena connected with the production, emission and detection of characteristic X-rays are discussed. This reference book addresses all researchers and practitioners working with X-ray radiation and fills a gap in the available literature.

  18. Typing Supernova Remnants Using X-ray Line Emission Morphologies

    CERN Document Server

    Lopez, Laura A; Badenes, Carles; Huppenkothen, Daniela; Jeltema, Tesla E; Pooley, David A

    2009-01-01

    We present a new observational method to type the explosions of young supernova remnants (SNRs). By measuring the morphology of the Chandra X-ray line emission in seventeen Galactic and Large Magellanic Cloud SNRs with a multipole expansion analysis (using power ratios), we find that the core-collapse SNRs are statistically more asymmetric than the Type Ia SNRs. We show that the two classes of supernovae can be separated naturally using this technique because X-ray line morphologies reflect the distinct explosion mechanisms and structure of the circumstellar material. These findings are consistent with recent spectropolarimetry results showing that core-collapse SNe are intrinsically more asymmetric.

  19. X-Ray Emission from the Halo of M31

    Science.gov (United States)

    Mushotzky, Richard (Technical Monitor); DiStefano, Rosanne

    2004-01-01

    Our goal was to use short (10 ksec) observations of selected fields in the halo of M31, to determine the size and characteristics of its X-ray population and to study the connection between globular clusters and X-ray sources. The program of observations has yet to be successfully completed. We received acceptable data from just 2 of the 5 approved fields. Nevertheless, the results were intriguing and we have submitted a paper based on this data to Nature. We find that the X-ray source density is significantly enhanced in the vicinity of one GC, providing the first observational evidence supporting the ejection hypothesis. We also find additional X-ray sources, including some which are very soft, in large enough numbers to suggest that not all could have been formed in GCs. That is, some must be descended from the same primordial halo population that produced any compact stars comprising part of the halo's dark matter. Extrapolating fiom the X-ray source population, we estimate that stellar remnants and dim old stars in the halo could comprise as much as 25% of the estimated mass (approx. 10(exp 12) Solar Mass) of the halo. These results suggest that the other approved fields should be observed soon and also provide strong motivation for the future XMM-Newton programs.

  20. X-ray data booklet. Revision

    Energy Technology Data Exchange (ETDEWEB)

    Vaughan, D. (ed.)

    1986-04-01

    A compilation of data is presented. Included are properties of the elements, electron binding energies, characteristic x-ray energies, fluorescence yields for K and L shells, Auger energies, energy levels for hydrogen-, helium-, and neonlike ions, scattering factors and mass absorption coefficients, and transmission bands of selected filters. Also included are selected reprints on scattering processes, x-ray sources, optics, x-ray detectors, and synchrotron radiation facilities. (WRF)

  1. Topological X-Rays and MRIs

    Science.gov (United States)

    Lynch, Mark

    2002-01-01

    Let K be a compact subset of the interior of the unit disk D in the plane and suppose one can't see through the boundary of D and identify K. However, assume that one can take "topological X-rays" of D which measure the "density" of K along the lines of the X-rays. By taking these X-rays from all directions, a "topological MRI" is generated for…

  2. Communication of Unexpected and Significant Findings on Chest Radiographs With an Automated PACS Alert System.

    LENUS (Irish Health Repository)

    Hayes, Sara A

    2014-08-01

    An integral part of realizing the enormous potential of imaging in patient care is close communication between radiologists and referring physicians. One key element of this process is the communication of unexpected significant findings. The authors examined the performance of a PACS-based alert system in the appropriate communication of reports containing unexpected significant findings to referring physicians.

  3. Observation of femtosecond X-ray interactions with matter using an X-ray-X-ray pump-probe scheme.

    Science.gov (United States)

    Inoue, Ichiro; Inubushi, Yuichi; Sato, Takahiro; Tono, Kensuke; Katayama, Tetsuo; Kameshima, Takashi; Ogawa, Kanade; Togashi, Tadashi; Owada, Shigeki; Amemiya, Yoshiyuki; Tanaka, Takashi; Hara, Toru; Yabashi, Makina

    2016-02-01

    Resolution in the X-ray structure determination of noncrystalline samples has been limited to several tens of nanometers, because deep X-ray irradiation required for enhanced resolution causes radiation damage to samples. However, theoretical studies predict that the femtosecond (fs) durations of X-ray free-electron laser (XFEL) pulses make it possible to record scattering signals before the initiation of X-ray damage processes; thus, an ultraintense X-ray beam can be used beyond the conventional limit of radiation dose. Here, we verify this scenario by directly observing femtosecond X-ray damage processes in diamond irradiated with extraordinarily intense (∼10(19) W/cm(2)) XFEL pulses. An X-ray pump-probe diffraction scheme was developed in this study; tightly focused double-5-fs XFEL pulses with time separations ranging from sub-fs to 80 fs were used to excite (i.e., pump) the diamond and characterize (i.e., probe) the temporal changes of the crystalline structures through Bragg reflection. It was found that the pump and probe diffraction intensities remain almost constant for shorter time separations of the double pulse, whereas the probe diffraction intensities decreased after 20 fs following pump pulse irradiation due to the X-ray-induced atomic displacement. This result indicates that sub-10-fs XFEL pulses enable conductions of damageless structural determinations and supports the validity of the theoretical predictions of ultraintense X-ray-matter interactions. The X-ray pump-probe scheme demonstrated here would be effective for understanding ultraintense X-ray-matter interactions, which will greatly stimulate advanced XFEL applications, such as atomic structure determination of a single molecule and generation of exotic matters with high energy densities.

  4. The efficacy of x-ray pelvimetry

    Energy Technology Data Exchange (ETDEWEB)

    Barton, J.J. (Univ. of Illinois, Chicago); Garbaciak, J.A. Jr.; Ryan, G.M., Jr.

    1982-06-01

    Comparison is made of x-ray pelvimetry use on a public and private service in 1974 with experience in 1979, when the clinic service did no x-ray pelvimetry while the private service continued as before. It is concluded that the use of x-ray pelvimetry is inadequate as a predictor of cesarean section because of cephalopelvic disproportion, does not improve neonatal mortality, and poses potential hazards to the mother and fetus. Its use in the management of breech presentations is not currently established by our data. Guidelines are presented for the management of patients in labor without using x-ray pelvimetry.

  5. Ultrashort X-ray pulse science

    Energy Technology Data Exchange (ETDEWEB)

    Chin, Alan Hap [Univ. of California, Berkeley, CA (US). Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    1998-05-01

    A variety of phenomena involves atomic motion on the femtosecond time-scale. These phenomena have been studied using ultrashort optical pulses, which indirectly probe atomic positions through changes in optical properties. Because x-rays can more directly probe atomic positions, ultrashort x-ray pulses are better suited for the study of ultrafast structural dynamics. One approach towards generating ultrashort x-ray pulses is by 90{sup o} Thomson scattering between terawatt laser pulses and relativistic electrons. Using this technique, the author generated {approx} 300 fs, 30 keV (0.4 {angstrom}) x-ray pulses. These x-ray pulses are absolutely synchronized with ultrashort laser pulses, allowing femtosecond optical pump/x-ray probe experiments to be performed. Using the right-angle Thomson scattering x-ray source, the author performed time-resolved x-ray diffraction studies of laser-perturbated InSb. These experiments revealed a delayed onset of lattice expansion. This delay is due to the energy relaxation from a dense electron-hole plasma to the lattice. The dense electron-hole plasma first undergoes Auger recombination, which reduces the carrier concentration while maintaining energy content. Longitudinal-optic (LO) phonon emission then couples energy to the lattice. LO phonon decay into acoustic phonons, and acoustic phonon propagation then causes the growth of a thermally expanded layer. Source characterization is instrumental in utilizing ultrashort x-ray pulses in time-resolved x-ray spectroscopies. By measurement of the electron beam diameter at the generation point, the pulse duration of the Thomson scattered x-rays is determined. Analysis of the Thomson scattered x-ray beam properties also provides a novel means of electron bunch characterization. Although the pulse duration is inferred for the Thomson scattering x-ray source, direct measurement is required for other x-ray pulse sources. A method based on the laser-assisted photoelectric effect (LAPE) has

  6. An Imaging X-Ray Polarimetry Mission

    Science.gov (United States)

    Weisskopf, Martin C.; Bellazini, Ronaldo; Costa, Enrico; Ramsey, Brian; O'Dell, Steve; Elsner, Ronald; Pavlov, George; Matt, Giorgio; Kaspi, Victoria; Tennant, Allyn; Coppi, Paolo; Wu, Kinwah; Siegmund, Oswald

    2008-01-01

    Technical progress both in x-ray optics and in polarization-sensitive x-ray detectors, which our groups have pioneered, enables a scientifically powerful---yet inexpensive---dedicated mission for imaging x-ray polarimetry. Such a mission is sufficiently sensitive to measure x-ray (linear) polarization for a broad range of cosmic sources --particularly those involving neutron stars, stellar black holes, and supermassive black holes (active galactic nuclei). We describe the technical elements, discuss a mission concept, and synopsize the important physical and astrophysical questions such a mission would address.

  7. Low Energy X-Ray Diagnostics - 1981.

    Science.gov (United States)

    1981-01-01

    appreciable back- [25] G. L. Johnson and R. F. Wuerker, X - RayO cs and ground at the diffraction line. It is for this reason X -Ray Microanalysis (Academic...I A-0AIIG 93 AWERICAN INST OF PHYSICS NEW YORK F/6 14/2 LOW ENERGY X -RAY DIAGNOSTICS - 1981.(U) 1961 D T ATTWOOO. 8 L HENKE AFOSAt-?SSA-61-00ORZN...RESOLUTION TEST CHART NATIONAl RJRAL AU M ’IAN[I)ARDS I ,* A Focusing, Filtering, and Scattering of V. Rehn Soft X -Rays by Mirrors 162 Synthetic

  8. Hard X-ray Modulation Telescope

    Institute of Scientific and Technical Information of China (English)

    LU Fangjun

    2011-01-01

    The Hard X-ray Modulation Telescope (HXMT) will be China's first astronomical satellite. On board HXMT there are three kinds of slat-collimated telescopes, the High Energy X-ray Telescope (HE, 20-250 keV, 5000 cm^2), the Medium Energy X-ray Telescope (ME, 5-30 keV, 952 cm^2), and the Low Energy X-ray Telescope (LE, 1-15 keV, 384 cm^2).

  9. X-rays from the youngest stars

    Science.gov (United States)

    Feigelson, Eric D.

    1994-01-01

    The X-ray properties of classical and weak-lined T Tauri stars are briefly reviewed, emphasizing recent results from the ROSAT satellite and prospects for ASCA. The interpretation of the high level of T Tauri X-rays as enhanced solar-type magnetic activity is discussed and criticized. The census of X-ray emitters is significantly increasing estimates of galactic star formation efficiency, and X-ray emission may be important for self-regulation of star formation. ASCA images will detect star formation regions out to several kiloparsecs and will study the magnetically heated plasma around T Tauri stars. However, images will often suffer from crowding effects.

  10. X-ray pulsar rush in 1998

    Energy Technology Data Exchange (ETDEWEB)

    Imanishi, K.; Tsujimoto, K.; Nishiuchi, Mamiko; Yokogawa, J.; Koyama, K. [Kyoto Univ., Faculty of Science, Kyoto (Japan)

    1999-08-01

    We present recent remarkable topics about discoveries of X-ray pulsars. 1. Pulsations from two Soft Gamma-ray Repeaters: These pulsars have enormously strong magnetic field (B {approx} 10{sup 15} G), thus these are called as 'magnetar', new type of X-ray pulsars. 2. New Crab-like pulsars: These discoveries lead to suggesting universality of Crab-like pulsars. 3. An X-ray bursting millisecond pulsar: This is strong evidence for the recycle theory of generating radio millisecond pulsars. 4. X-ray pulsar rush in the SMC: This indicates the younger star formation history in the SMC. (author)

  11. Unrequested imaging findings on routine chest CT : results from the PROVIDI study

    NARCIS (Netherlands)

    Gondrie, M.J.A.

    2011-01-01

    Prognostic research is of growing importance. However, rarely are results from imaging techniques considered for medical prognostication, whilst prognostically promising unrequested imaging findings are increasingly being detected in daily routine care. Therefore this thesis aimed to contribute to t

  12. Acute chest pain in emergency room. Preliminary findings with 40-64-slice CT ECG-gated of the whole chest.

    Science.gov (United States)

    Coche, E

    2007-01-01

    ECG-gated MDCT of the entire chest represents the latest technical advance in the diagnostic work-up of atypical chest pain. The authors report their preliminary experience with the use of 40 and 64-slice CT in the emergency room and recommend to study only patients with moderate likelihood of coronary artery disease. ECG-gated MDCT of the entire chest will be preferentially performed on 64-slice MDCT rather than 40-slice MDCT because it enable to reduce the scan time (18 seconds versus 28 seconds acquisition time), the volume of contrast medium (82 mL + 15 mL versus 97 mL + 15 mL of highly concentrated contrast agent for a patient of 70 kgs) and radiation exposure (17 mSv versus 19 mSv). Approximately 1500 to 2000 of images are produced and need to be analysed on a dedicated workstation by a radiologist expert in cardiac and thoracic disorders. At the present time, only a few studies exist in the literature showing some promising results but further large clinical studies are needed before to implement such sophisticated protocol in emergency room.

  13. The First Stars: formation under X-ray feedback

    CERN Document Server

    Hummel, Jacob A; Jeon, Myoungwon; Oliveri, Anthony; Bromm, Volker

    2014-01-01

    We investigate the impact of an ionising X-ray background on metal-free Population III stars within a minihalo at $z\\simeq25$ starting from cosmological initial conditions. Using the smoothed particle hydrodynamics code GADGET-2, we attain sufficient numerical resolution to follow the gas collapsing into the centre of the minihalo up to densities of $n=10^{12}\\,cm^{-3}$, at which point we form sink particles. This allows us to study how the presence of a cosmic X-ray background (CXB) affects the formation of H$_2$ and HD in the gas before it becomes fully molecular. Using a suite of simulations for a range of possible CXB models, we follow each simulation for 5000 yr after the formation of the first sink particle. The CXB provides two competing effects, with X-rays both heating the gas and enhancing its ability to cool by increasing the free electron fraction, allowing more H$_2$ to form. We find that X-ray heating dominates below $n\\sim1\\,cm^{-3}$, while the additional cooling catalysed by X-ray ionisation b...

  14. [The application of X-ray imaging in forensic medicine].

    Science.gov (United States)

    Kučerová, Stěpánka; Safr, Miroslav; Ublová, Michaela; Urbanová, Petra; Hejna, Petr

    2014-07-01

    X-ray is the most common, basic and essential imaging method used in forensic medicine. It serves to display and localize the foreign objects in the body and helps to detect various traumatic and pathological changes. X-ray imaging is valuable in anthropological assessment of an individual. X-ray allows non-invasive evaluation of important findings before the autopsy and thus selection of the optimal strategy for dissection. Basic indications for postmortem X-ray imaging in forensic medicine include gunshot and explosive fatalities (identification and localization of projectiles or other components of ammunition, visualization of secondary missiles), sharp force injuries (air embolism, identification of the weapon) and motor vehicle related deaths. The method is also helpful for complex injury evaluation in abused victims or in persons where abuse is suspected. Finally, X-ray imaging still remains the gold standard method for identification of unknown deceased. With time modern imaging methods, especially computed tomography and magnetic resonance imaging, are more and more applied in forensic medicine. Their application extends possibilities of the visualization the bony structures toward a more detailed imaging of soft tissues and internal organs. The application of modern imaging methods in postmortem body investigation is known as digital or virtual autopsy. At present digital postmortem imaging is considered as a bloodless alternative to the conventional autopsy.

  15. X-ray states of redback millisecond pulsars

    CERN Document Server

    Linares, Manuel

    2014-01-01

    Compact binary millisecond pulsars with main-sequence donors, often referred to as "redbacks", constitute the long-sought link between low-mass X-ray binaries and millisecond radio pulsars, and offer a unique probe of the interaction between pulsar winds and accretion flows. We present a systematic study of eight nearby redbacks, using more than 100 observations obtained with Swift's X-ray Telescope. We distinguish between three main states: pulsar, disk and outburst states. We find X-ray mode switching in the disk state of PSR J1023+0038 and XSS J12270-4859, similar to what was found in the other redback which showed evidence for accretion: rapid, recurrent changes in X-ray luminosity (0.5-10 keV, L$_\\mathrm{X}$), between [6-9]$\\times$10$^{32}$ erg s$^{-1}$ (disk-passive state) and [3-5]$\\times$10$^{33}$ erg s$^{-1}$ (disk-active state). This strongly suggests that mode switching $-$which has not been observed in quiescent low-mass X-ray binaries$-$ is universal among redback millisecond pulsars in the disk ...

  16. Symbiotic stars in X-rays III: Suzaku observations

    CERN Document Server

    Nuñez, N E; Mukai, K; Sokoloski, J L; Luna, G J M

    2016-01-01

    We describe the X-ray emission as observed with Suzaku from five symbiotic stars that we selected for deep Suzaku observations after their initial detection with ROSAT, ASCA and Swift. We find that the X-ray spectra of all five sources can be adequately fit with absorbed, optically thin thermal plasma models, with either single- or multi-temperature plasmas. These models are compatible with the X-ray emission originating in the boundary layer between an accretion disk and a white dwarf. The high plasma temperatures of kT$~>3$ keV for all five targets were greater than expected for colliding winds. Based on these high temperatures, as well as previous measurements of UV variability and UV luminosity, and the large amplitude of X-ray flickering in 4 Dra, we conclude that all five sources are accretion-powered through predominantly optically thick boundary layers. Our X-ray data allow us to observe a small, optically thin portion of the emission from these boundary layers. Given the time between previous observa...

  17. Eclipsing the innermost X-ray emitting regions in AGN

    CERN Document Server

    Sanfrutos, Mario; Dovčiak, Michal; Agís-González, Beatriz

    2015-01-01

    Variable X-ray absorption has been observed in active galactic nuclei (AGN) on several time scales. Observations allow us to identify the absorber with clouds associated either with the clumpy torus (parsec scales, long timescales) or with the broad line region (BLR) (short timescales). In the latter, the cloud size has been estimated to be of the order of few gravitational radii from the observed absorption variability. Such small cloud sizes are comparable to the X-ray emitting regions so that a detailed modeling of occultation events in AGN has the potential of enabling us to infer accurately the geometry of the system. We have developed a relativistic X-ray spectral model for occultation events and we present here theoretical predictions on the different observables that can be inferred by studying X-ray eclipses in simulated XMM-Newton data. These include the size of the X-ray emitting regions as well as more fundamental parameters such as the black hole spin and the system inclination. We find that abso...

  18. X-ray computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kalender, Willi A [Institute of Medical Physics, University Erlangen-Nuernberg, Henkestr. 91, D-91052 Erlangen (Germany)

    2006-07-07

    X-ray computed tomography (CT), introduced into clinical practice in 1972, was the first of the modern slice-imaging modalities. To reconstruct images mathematically from measured data and to display and to archive them in digital form was a novelty then and is commonplace today. CT has shown a steady upward trend with respect to technology, performance and clinical use independent of predictions and expert assessments which forecast in the 1980s that it would be completely replaced by magnetic resonance imaging. CT not only survived but exhibited a true renaissance due to the introduction of spiral scanning which meant the transition from slice-by-slice imaging to true volume imaging. Complemented by the introduction of array detector technology in the 1990s, CT today allows imaging of whole organs or the whole body in 5 to 20 s with sub-millimetre isotropic resolution. This review of CT will proceed in chronological order focussing on technology, image quality and clinical applications. In its final part it will also briefly allude to novel uses of CT such as dual-source CT, C-arm flat-panel-detector CT and micro-CT. At present CT possibly exhibits a higher innovation rate than ever before. In consequence the topical and most recent developments will receive the greatest attention. (review)

  19. SMM X-ray polychromator

    Science.gov (United States)

    Strong, Keith T.; Haisch, Bernhard M. (Compiler); Lemen, James R. (Compiler); Acton, L. W.; Bawa, H. S.; Claflin, E. S.; Freeland, S. L.; Slater, G. L.; Kemp, D. L.; Linford, G. A.

    1988-01-01

    The range of observing and analysis programs accomplished with the X-Ray Polychromator (XRP) instruments during the decline of solar cycle 21 and the rise of the solar cycle 22 is summarized. Section 2 describes XRP operations and current status. This is meant as a guide on how the instrument is used to obtain data and what its capabilities are for potential users. The science section contains a series of representative abstracts from recently published papers on major XRP science topics. It is not meant to be a complete list but illustrates the type of science that can come from the analysis of the XRP data. There then follows a series of appendixes that summarize the major data bases that are available. Appendix A is a complete bibliography of papers and presentations produced using XRP data. Appendix B lists all the spectroscopic data accumulated by the Flat Crystal Spectrometer (FCS). Appendix C is a compilation of the XRP flare catalogue for events equivalent to a GOES C-level flare or greater. It lists the start, peak and end times as well as the peak Ca XIX flux.

  20. Radiological findings of chest in patients with H7N9 avian influenza from a hospital

    Directory of Open Access Journals (Sweden)

    Huanjie Ma

    2015-12-01

    Conclusion: With the right lower lobe prominence, the main abnormal findings in H7N9 pneumonia include rapidly progressive GGOs, consolidations with air bronchograms, and pleural effusion. CT imaging may provide a more accurate assessment of the lung pathology with H7N9 avian influenza, helping the early diagnosis and monitoring its progression.

  1. The X-Ray View of OB Star Wind Structure and Dynamics

    Science.gov (United States)

    Cohen, D. H.

    2012-12-01

    High-resolution X-ray grating spectroscopy enables us to measure the kinematics and spatial distribution of the shock-heated wind plasma in O and early B stars, testing the predictions of the embedded wind shock scenario of massive star X-ray production. By fitting models to the resolved, Doppler broadened X-ray emission line profiles measured by the Chandra X-ray Observatory's grating spectrometer, we find an onset radius of X-ray production of roughly Ro = 1.5 R★ for the O supergiants, ζ Pup and HD 93129A. From the profile fitting we also find that the terminal velocity of the X-ray emitting plasma is consistent with that of the bulk, UV absorbing wind. We also use the X-ray emission line profiles to measure the wind mass-loss rates and break the degeneracy between mass-loss rate and clumping factor that affects traditional Hα and radio free-free diagnostics. We find clumping factors of order fcl = 10, which also agrees with the simulations of the wind instability. And we find that clumping begins very close to the photosphere, significantly lower in the wind than the onset of X-ray production. For lower density B star winds, the X-ray emission lines are much narrower than in the O supergiants, and are inconsistent with the hot plasma sharing the kinematics of the bulk wind.

  2. Einstein X-ray observations of Herbig Ae/Be stars

    Science.gov (United States)

    Damiani, F.; Micela, G.; Sciortino, S.; Harnden, F. R., Jr.

    1994-01-01

    We have investigated the X-ray emission from Herbig Ae/Be stars, using the full set of Einstein Imaging Proportional Counter (IPC) observations. Of a total of 31 observed Herbig stars, 11 are confidently identified with X-ray sources, with four additonal dubious identifications. We have used maximum likelihood luminosity functions to study the distribution of X-ray luminosity, and we find that Be stars are significantly brighter in X-rays than Ae stars and that their X-ray luminosity is independent of projected rotational velocity v sin i. The X-ray emission is instead correlated with stellar bolometric luminosity and with effective temperature, and also with the kinetic luminosity of the stellar wind. These results seem to exclude a solar-like origin for the X-ray emission, a possibility suggested by the most recent models of Herbig stars' structure, and suggest an analogy with the X-ray emission of O (and early B) stars. We also observe correlations between X-ray luminosity and the emission at 2.2 microns (K band) and 25 microns, which strengthen the case for X-ray emission of Herbig stars originating in their circumstellar envelopes.

  3. Extrasolar Giant Planets and X-ray Activity

    CERN Document Server

    Kashyap, Vinay L; Saar, Steven H

    2008-01-01

    We have carried out a survey of X-ray emission from stars with giant planets, combining both archival and targeted surveys. Over 230 stars have been currently identified as possessing planets, and roughly a third of these have been detected in X-rays. We carry out detailed statistical analysis on a volume limited sample of main sequence star systems with detected planets, comparing subsamples of stars that have close-in planets with stars that have more distant planets. This analysis reveals strong evidence that stars with close-in giant planets are on average more X-ray active by a factor ~4 than those with planets that are more distant. This result persists for various sample selections. We find that even after accounting for observational sample bias, a significant residual difference still remains. This observational result is consistent with the hypothesis that giant planets in close proximity to the primary stars influences the stellar magnetic activity.

  4. Impulsive X-ray Raman excitation of NO$_2$

    CERN Document Server

    Haxton, Daniel J

    2016-01-01

    We investigate impulsive X-ray Raman excitation of the NO$_2$ molecule. We seek to optimize population transfer to valence states of the NO$_2$ molecule using using 1fs pulses tuned below the Oxygen K-edge, and detect subsequent coherent electron motion among valence excited states by using a second, weak X-ray pulse with variable time delay that ionizes a Nitrogen 1$s$ electron. Toward these ends, impulsive X-ray Raman excitations were calculated in the fixed-nuclei approximation using the multiconfiguration time-dependent Hartree-Fock (MCTDHF) method. Fixing the duration but varying the central frequency and intensity of the pulse, not considering chirp, we find optimum population transfer at intensity approximately 3$\\times$10$^{17}$ W cm$^{-2}$, an intensity for which 2nd order pertubation theory is no longer applicable, with the central frequency substantially 8eV red-detuned from the 2nd order optimum.

  5. X-Ray Shadowing Experiments Toward Infrared Dark Clouds

    Science.gov (United States)

    Anderson, L. E.; Snowden, S.; Bania, T. M.

    2009-01-01

    We searched for X-ray shadowing toward two infrared dark clouds (IRDCs) using the MOS detectors on XMM-Newton to learn about the Galactic distribution of X-ray emitting plasma. IRDCs make ideal X-ray shadowing targets of 3/4 keY photons due to their high column densities, relatively large angular sizes, and known kinematic distances. Here we focus on two clouds near 30 deg Galactic longitude at distances of 2 and 5 kpc from the Sun. We derive the foreground and background column densities of molecular and atomic gas in the direction of the clouds. We find that the 3/4 ke V emission must be distributed throughout the Galactic disk. It is therefore linked to the structure of the cooler material of the ISM, and to the birth of stars.

  6. Diffraction leveraged modulation of X-ray pulses using MEMS-based X-ray optics

    Science.gov (United States)

    Lopez, Daniel; Shenoy, Gopal; Wang, Jin; Walko, Donald A.; Jung, Il-Woong; Mukhopadhyay, Deepkishore

    2016-08-09

    A method and apparatus are provided for implementing Bragg-diffraction leveraged modulation of X-ray pulses using MicroElectroMechanical systems (MEMS) based diffractive optics. An oscillating crystalline MEMS device generates a controllable time-window for diffraction of the incident X-ray radiation. The Bragg-diffraction leveraged modulation of X-ray pulses includes isolating a particular pulse, spatially separating individual pulses, and spreading a single pulse from an X-ray pulse-train.

  7. Screening in resonant X-ray emission of molecules

    DEFF Research Database (Denmark)

    Ågren, Hans; Luo, Yi; Gelmukhanov, Faris;

    1996-01-01

    We explore the effects of screening in resonant X-ray emission from molecules by means of unconstrained multi-configurational self-consistent field optimizations of each state involved in the resonant and nonresonant X-ray processes. It is found that, although screening can produce shifts...... in transition energies of a few eV, its effect on the transition intensities is relatively minor. Using results from the investigated molecules, we find that the screening is quite dependent on the type of molecule - saturated versus unsaturated - and on the core site, but depends little on the particular core...

  8. The missing Wolf-Rayet X-ray binary systems

    Science.gov (United States)

    Munoz, M.; Moffat, A. F. J.; Hill, G. M.; Richardson, N. D.; Pablo, H.

    We investigate the rarity of the Wolf-Rayet X-ray binaries (WRXRBs) in contrast to their predecessors, the high mass X-ray binaries (HMXRBs). Recent studies suggest that common envelope (CE) mergers during the evolution of a HMXRBs may be responsible (Linden et al. 2012). We conduct a binary population synthesis to generate a population of HMXRBs mimicking the Galactic sample and vary the efficiency parameter during the CE phase to match the current WRXRB to HMXRB ratio. We find that ˜50% of systems must merge to match observational constraints.

  9. Characteristics of ultrafast K line hard x-ray source from femtosecond terawatt laser-produced plasma

    Institute of Scientific and Technical Information of China (English)

    陈敏; 陈建文; 高鸿奕; 陆培祥; 徐至展

    2003-01-01

    Theoretical studies and analytical scalings were carried out to find the optimized laser parameters and target conditions so that ultrashort hard x-ray pulses and high x-ray power could be achieved. The dependence of laser intensity and wavelength on the yield of K-shell x-ray emission was studied. We propose an optimal design for a foil target for producing high-yield hard x-ray pulses of customizing duration.

  10. Can chest high-resolution computed tomography findings diagnose pulmonary alveolar microlithiasis?

    Energy Technology Data Exchange (ETDEWEB)

    Francisco, Flavia Angelica Ferreira; Rodrigues, Rosana Souza; Barreto, Miriam Menna; Zanetti, Glaucia [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Escuissato, Dante Luiz [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil); Araujo Neto, Cesar Augusto [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Dept. de Medicina e Apoio Diagnostico; Silva, Claudio S. [Radiology Department, Facultad de Medicina Clinica Alemana, Universidad del Desarrollo, Santiago (Chile); Hochhegger, Bruno [Universidade Federal de Ciencias da Saude de Porto Alegre (UFCSPA), Porto Alegre, RS (Brazil); Marchiori, Edson, E-mail: edmarchiori@gmail.com [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2015-07-15

    Objective: the present study was aimed at retrospectively reviewing high-resolution computed tomography (HRCT) findings in patients with pulmonary alveolar microlithiasis in order to evaluate the frequency of tomographic findings and their distribution in the lung parenchyma. Materials and methods: thirteen patients (9 females and 4 males; age, 9 to 59 years; mean age, 34.5 years) were included in the present study. The HRCT images were independently evaluated by two observers whose decisions were made by consensus. The inclusion criterion was the presence of abnormalities typical of pulmonary alveolar microlithiasis at HRCT, which precludes lung biopsy. However, in 6 cases lung biopsy was performed. Results: ground-glass opacities and small parenchymal nodules were the predominant tomographic findings, present in 100% of cases, followed by small subpleural nodules (92.3%), subpleural cysts (84.6%), subpleural linear calcifications (69.2%), crazy-paving pattern (69.2%), fissure nodularity (53.8%), calcification along interlobular septa (46.2%) and dense consolidation (46.2%). Conclusion: as regards distribution of the lesions, there was preferential involvement of the lower third of the lungs. No predominance of distribution in axial and anteroposterior directions was observed. (author)

  11. Accelerator-driven X-ray Sources

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Dinh Cong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-09

    After an introduction which mentions x-ray tubes and storage rings and gives a brief review of special relativity, the subject is treated under the following topics and subtopics: synchrotron radiation (bending magnet radiation, wiggler radiation, undulator radiation, brightness and brilliance definition, synchrotron radiation facilities), x-ray free-electron lasers (linac-driven X-ray FEL, FEL interactions, self-amplified spontaneous emission (SASE), SASE self-seeding, fourth-generation light source facilities), and other X-ray sources (energy recovery linacs, Inverse Compton scattering, laser wakefield accelerator driven X-ray sources. In summary, accelerator-based light sources cover the entire electromagnetic spectrum. Synchrotron radiation (bending magnet, wiggler and undulator radiation) has unique properties that can be tailored to the users’ needs: bending magnet and wiggler radiation is broadband, undulator radiation has narrow spectral lines. X-ray FELs are the brightest coherent X-ray sources with high photon flux, femtosecond pulses, full transverse coherence, partial temporal coherence (SASE), and narrow spectral lines with seeding techniques. New developments in electron accelerators and radiation production can potentially lead to more compact sources of coherent X-rays.

  12. X-raying clumped stellar winds

    CERN Document Server

    Oskinova, L M; Feldmeier, A

    2008-01-01

    X-ray spectroscopy is a sensitive probe of stellar winds. X-rays originate from optically thin shock-heated plasma deep inside the wind and propagate outwards throughout absorbing cool material. Recent analyses of the line ratios from He-like ions in the X-ray spectra of O-stars highlighted problems with this general paradigm: the measured line ratios of highest ions are consistent with the location of the hottest X-ray emitting plasma very close to the base of the wind, perhaps indicating the presence of a corona, while measurements from lower ions conform with the wind-embedded shock model. Generally, to correctly model the emerging X-ray spectra, a detailed knowledge of the cool wind opacities based on stellar atmosphere models is prerequisite. A nearly grey stellar wind opacity for the X-rays is deduced from the analyses of high-resolution X-ray spectra. This indicates that the stellar winds are strongly clumped. Furthermore, the nearly symmetric shape of X-ray emission line profiles can be explained if t...

  13. X-Ray Detection Visits the Classroom

    Science.gov (United States)

    Peralta, Luis; Farinha, Ana; Pinto, Ana

    2008-01-01

    Film has been used to detect x-rays since the early days of their discovery by Rontgen. Although nowadays superseded by other techniques, film still provides a cheap means of x-ray detection, making it attractive in high-school or undergraduate university courses. If some sort of quantitative result is required, the film's optical absorbance or…

  14. X-ray lasers: Multicolour emission

    Science.gov (United States)

    Feng, Chao; Deng, Haixiao

    2016-11-01

    The X-ray free-electron laser at the SLAC National Accelerator Laboratory in the US can now generate multicolour X-ray pulses with unprecedented brightness using the fresh-slice technique. The development opens the way to new forms of spectroscopy.

  15. New Insights into X-ray Binaries

    CERN Document Server

    Casares, Jorge

    2009-01-01

    X-ray binaries are excellent laboratories to study collapsed objects. On the one hand, transient X-ray binaries contain the best examples of stellar-mass black holes while persistent X-ray binaries mostly harbour accreting neutron stars. The determination of stellar masses in persistent X-ray binaries is usually hampered by the overwhelming luminosity of the X-ray heated accretion disc. However, the discovery of high-excitation emission lines from the irradiated companion star has opened new routes in the study of compact objects. This paper presents novel techniques which exploits these irradiated lines and summarises the dynamical masses obtained for the two populations of collapsed stars: neutron stars and black holes.

  16. X-ray Fourier ptychographic microscopy

    CERN Document Server

    Simons, H; Guigay, J P; Detlefs, C

    2016-01-01

    Following the recent developement of Fourier ptychographic microscopy (FPM) in the visible range by Zheng et al. (2013), we propose an adaptation for hard x-rays. FPM employs ptychographic reconstruction to merge a series of low-resolution, wide field of view images into a high-resolution image. In the x-ray range this opens the possibility to overcome the limited numerical aperture of existing x-ray lenses. Furthermore, digital wave front correction (DWC) may be used to charaterize and correct lens imperfections. Given the diffraction limit achievable with x-ray lenses (below 100 nm), x-ray Fourier ptychographic microscopy (XFPM) should be able to reach resolutions in the 10 nm range.

  17. X-ray diffraction: instrumentation and applications.

    Science.gov (United States)

    Bunaciu, Andrei A; Udriştioiu, Elena Gabriela; Aboul-Enein, Hassan Y

    2015-01-01

    X-ray diffraction (XRD) is a powerful nondestructive technique for characterizing crystalline materials. It provides information on structures, phases, preferred crystal orientations (texture), and other structural parameters, such as average grain size, crystallinity, strain, and crystal defects. X-ray diffraction peaks are produced by constructive interference of a monochromatic beam of X-rays scattered at specific angles from each set of lattice planes in a sample. The peak intensities are determined by the distribution of atoms within the lattice. Consequently, the X-ray diffraction pattern is the fingerprint of periodic atomic arrangements in a given material. This review summarizes the scientific trends associated with the rapid development of the technique of X-ray diffraction over the past five years pertaining to the fields of pharmaceuticals, forensic science, geological applications, microelectronics, and glass manufacturing, as well as in corrosion analysis.

  18. LOBSTER - New Space X-Ray telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Hudec, R. [Astronomical Institute, Academy of Sciences of the Czech Republic, CZ-251 65 Ondrejov (Czech Republic); Pina, L. [Faculty of Nuclear Science, Czech Technical University, Prague (Czech Republic); Simon, V. [Astronomical Institute, Academy of Sciences of the Czech Republic, CZ-251 65 Ondrejov (Czech Republic); Sveda, L. [Faculty of Nuclear Science, Czech Technical University, Prague (Czech Republic); Inneman, A.; Semencova, V. [Center for Advanced X-ray Technologies, Reflex, Prague (Czech Republic); Skulinova, M. [Astronomical Institute, Academy of Sciences of the Czech Republic, CZ-251 65 Ondrejov (Czech Republic)

    2007-04-15

    We discuss the technological and scientific aspects of fully innovative very wide-field X-ray telescopes with high sensitivity. The prototypes of Lobster telescopes designed, developed and tested are very promising, allowing the proposals for space projects with very wide-field Lobster Eye X-ray optics to be considered for the first time. The novel telescopes will monitor the sky with unprecedented sensitivity and angular resolution of order of 1 arcmin. They are expected to contribute essentially to study of various astrophysical objects such as AGN, SNe, Gamma-ray bursts (GRBs), X-ray flashes (XRFs), galactic binary sources, stars, CVs, X-ray novae, various transient sources, etc. For example, the Lobster optics based X-ray All Sky Monitor is capable to detect around 20 GRBs and 8 XRFs yearly and this will surely significantly contribute to the related science.

  19. Globular Cluster X-ray Sources

    CERN Document Server

    Verbunt, F

    2004-01-01

    After a brief historical overview we discuss the luminous X-ray sources in globular clusters of our Galaxy. This is followed by an overview of the very luminous X-ray sources studied in globular clusters of 14 other galaxies, and a discussion of their formation and the relation to X-ray sources outside globular clusters. We describe the discovery and classification of low-luminosity X-ray sources, and end the review with some remarks on the formation and evolution of X-ray sources in globular clusters. Observational results are summarized in three tables. Comments are very welcome. Please send them to F.W.M.Verbunt@astro.uu.nl and lewin@mit.edu.

  20. High Energy Vision: Processing X-rays

    CERN Document Server

    DePasquale, Joseph; Edmonds, Peter

    2015-01-01

    Astronomy is by nature a visual science. The high quality imagery produced by the world's observatories can be a key to effectively engaging with the public and helping to inspire the next generation of scientists. Creating compelling astronomical imagery can, however, be particularly challenging in the non-optical wavelength regimes. In the case of X-ray astronomy, where the amount of light available to create an image is severely limited, it is necessary to employ sophisticated image processing algorithms to translate light beyond human vision into imagery that is aesthetically pleasing while still being scientifically accurate. This paper provides a brief overview of the history of X-ray astronomy leading to the deployment of NASA's Chandra X-ray Observatory, followed by an examination of the specific challenges posed by processing X-ray imagery. The authors then explore image processing techniques used to mitigate such processing challenges in order to create effective public imagery for X-ray astronomy. ...

  1. X-Rays from Green Pea Analogs

    Science.gov (United States)

    Brorby, Matthew

    2014-09-01

    X-rays may have contributed to the heating and reionization of the IGM in the early universe. High mass X-ray binaries (HMXB) within small, low-metallicity galaxies are expected to be the main source of X-rays at this time. Since studying these high-redshift galaxies is currently impossible, we turn to local analogs that have the same properties the galaxies in the early are expected to have. A number of recent studies have shown an enhanced number of HMXBs in nearby low metallicity galaxies. We propose to observe a sample of metal-deficient luminous compact galaxies (LCG) in order to determine if the X-ray luminosity is enhanced relative to SFR, thereby providing further evidence to the importance of X-rays in the early universe.

  2. An X-ray view of quasars

    CERN Document Server

    Singh, K P

    2013-01-01

    I present an overview of observational studies of quasars of all types, with particular emphasis on X-ray observational studies. The presentation is based on the most popularly accepted unified picture of quasars - collectively referred to as AGN (active galactic nuclei) in this review. Characteristics of X-ray spectra and X-ray variability obtained from various X-ray satellites over the last 5 decades have been presented and discussed. The contribution of AGN in understanding the cosmic X-ray background is discussed very briefly. Attempt has been made to provide up-to-date information; however, this is a vast subject and this presentation is not intended to be comprehensive.

  3. Pulmonary infection caused by Mycobacterium kansasii: findings on computed tomography of the chest

    Energy Technology Data Exchange (ETDEWEB)

    Mogami, Roberto; Lopes, Agnaldo Jose; Marca, Patricia Gomes Cytrangulo de, E-mail: agnaldolopes.uerj@gmail.com [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil); Goldenberg, Telma; Mello, Fernanda Carvalho de Queiroz [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)

    2016-07-15

    Objective: To describe the main tomography findings in patients diagnosed with pulmonary infection caused by Mycobacterium kansasii. Materials and Methods: Retrospective study of computed tomography scans of 19 patients with pulmonary infection by M. kansasii. Results: Of the 19 patients evaluated, 10 (52.6%) were male and 9 (47.4%) were female. The mean age of the patients was 58 years (range, 33-76 years). Computed tomography findings were as follows: architectural distortion, in 17 patients (89.5%); reticular opacities and bronchiectasis, in 16 (84.2%); cavities, in 14 (73.7%); centrilobular nodules, in 13 (68.4%); small consolidations, in 10 (52.6%); atelectasis and large consolidations, in 9 (47.4%); subpleural blebs and emphysema, in 6 (31.6%); and adenopathy, in 1 (5.3%). Conclusion: There was a predominance of cavities, as well as of involvement of the small and large airways. The airway disease was characterized by bronchiectasis and bronchiolitis presenting as centrilobular nodules. (author)

  4. Pulmonary infection caused by Mycobacterium kansasii: findings on computed tomography of the chest*

    Science.gov (United States)

    Mogami, Roberto; Goldenberg, Telma; de Marca, Patricia Gomes Cytrangulo; Mello, Fernanda Carvalho de Queiroz; Lopes, Agnaldo José

    2016-01-01

    Objective To describe the main tomography findings in patients diagnosed with pulmonary infection caused by Mycobacterium kansasii. Materials and Methods Retrospective study of computed tomography scans of 19 patients with pulmonary infection by M. kansasii. Results Of the 19 patients evaluated, 10 (52.6%) were male and 9 (47.4%) were female. The mean age of the patients was 58 years (range, 33-76 years). Computed tomography findings were as follows: architectural distortion, in 17 patients (89.5%); reticular opacities and bronchiectasis, in 16 (84.2%); cavities, in 14 (73.7%); centrilobular nodules, in 13 (68.4%); small consolidations, in 10 (52.6%); atelectasis and large consolidations, in 9 (47.4%); subpleural blebs and emphysema, in 6 (31.6%); and adenopathy, in 1 (5.3%). Conclusion There was a predominance of cavities, as well as of involvement of the small and large airways. The airway disease was characterized by bronchiectasis and bronchiolitis presenting as centrilobular nodules. PMID:27777472

  5. Chest radiographic findings in children with 2009 influenza A ( H1N1 ) virus infection%2009甲型H1N1流感儿童胸X线片表现

    Institute of Scientific and Technical Information of China (English)

    闫淯淳; 房萍; 白凤森; 陈慧中; 车莉; 袁新宇; 曲东; 任晓旭; 张宝元; 孙宇

    2011-01-01

    Objective To evaluate chest radiographic findings of children with 2009 influenza ( H1N1 ) virus infection. Method Data of 235 patients who had microbiologically confirmed H1N1 infection and available chest radiograph obtained between May 1st 2009 and Jan. 31st 2010 were retrospectively analyzed. The final study group was divided on the basis of clinical course [group 1 mild, outpatients without hospitalization ( n = 172 ); group 2 moderate, inpatients with brief hospitalization ( n = 49 ); group 3 severe, ICU admission (n = 14)]. Four pediatric radiologists reviewed all the chest radiographs of lung parenchyma, airway, pleural abnormalities and also anatomic distribution of the disease. Result No significant sex or age differences were found among the study groups ( P >0.05 ). The mean interval between the onset of clinical symptom and the initial chest radiography was (5.91 ± 1. 64) days (group 1 ), (3.60 ±1.43 ) days ( group 2) and ( 1.21 ± 0.41 ) days ( group 3 ), respectively. The differences among the three groups were significant statistically ( χ2 = 13.368, P < 0.01 ). The ratio of abnormality presented at initial chest X-ray was 79.7% in group 1,91.8% in group 2 and 100% in group 3. Radiographically, there were prominent peribronchial markings ( group 1, 55.2%; group 2, 83.7%; and group 3, 78.6% ),consolidation ( group 1, 34.3%; group 2, 69.4%; and group 3, 100.0% ), hyperinflation ( group 1,22.1%; group 2, 44.9%; and group 3, 50.0% ) and ground glass opacity ( group 1, 0.6%; group 2,2.0%; and group 3, 14.3% ) in the chest radiographs. The differences of presenting were statistically significant (P <0.01 ). In the severe group, the lesions distributed diffusely and asymmetrically with multi lobe involvements. Conclusion In children with 2009 influenza A H1N1 viral infection, the interval between the onset of clinical symptom and initial chest radiography, the ratio of abnormality presented at initial chest X-ray film and the severity of chest

  6. Novel influenza A (H1N1) infection: chest CT findings from 21 cases in Seoul, Korea

    Energy Technology Data Exchange (ETDEWEB)

    Shim, S.S., E-mail: sinisim@ewha.ac.k [Department of Diagnostic Radiology and Center for Imaging Science, Mokdong Hospital, Ewha Womans University School of Medicine, Seoul (Korea, Republic of); Kim, Y. [Department of Diagnostic Radiology and Center for Imaging Science, Mokdong Hospital, Ewha Womans University School of Medicine, Seoul (Korea, Republic of); Ryu, Y.J. [Division of Pulmonary and Critical care medicine, Department of Internal Medicine, Mokdong Hospital, Ewha Womans University School of Medicine, Seoul (Korea, Republic of)

    2011-02-15

    Aim: To retrospectively evaluate the computed tomography (CT) appearances of novel influenza A (H1N1) infection. Materials and methods: Chest CT images obtained at clinical presentation in 21 patients (eight men, 13 women; mean age, 37 years; age range, 6-82 years) with confirmed novel influenza A (H1N1) infection were assessed. The radiological appearances of pulmonary parenchymal abnormalities, distribution, and extent of involvement on initial chest CT images were documented. The study group was divided on the basis of age [group 1, patients <18 years old (n = 8); group 2, patients {>=}18 years old (n = 13)]. Medical records were reviewed for underlying medical conditions and laboratory findings. The occurrence of recognizable CT patterns was compared for each group using the images from the initial CT examination. Results: The most common CT pattern observed in all patients was ground-glass attenuated (GGA) lesions (20/21, 95%). Bronchial wall thickening (9/21, 43%) was the second most common CT finding. Other common CT findings were consolidation (6/21, 29%), pleural effusion (6/21, 29%), pneumothorax or pneumomediastinum (5/21, 24%), and atelectasis (5/21, 24%). Among these, atelectasis and pneumomediastinum (pneumothorax) were only observed in group 1. The GGA lesions showed predilections for diffuse multifocal (10/20, 50%) or lower zone (8/20, 40%) distribution. Involvement of central lung parenchyma (12/20, 60%) was more common than a mixed peripheral and central pattern (6/20, 30%) or a subpleural pattern (2/20, 10%) at the time of presentation. Patchy GGA lesions were more frequent (18/20, 90%) than diffuse GGA lesions, and 75% (15/20) of these lesions had a bronchovascular distribution. Bilateral disease was present in all patients with GGA lesions. Bronchial wall thickening was predominantly centrally located and the distribution of the consolidation was non-specific. Conclusion: The predominantly centrally located GGA lesions, with common multifocal

  7. Development and tests of x-ray multifoil optical system for 1D imaging (Conference Presentation)

    Science.gov (United States)

    Pína, Ladislav; Hudec, René; Inneman, Adolf J.; Baca, Tomas; Blazek, M.; Platkevic, M.; Sieger, Ladislav; Doubravova, Daniela; McEntaffer, Randall L.; Schultz, Ted B.; Dániel, Vladimír.

    2016-09-01

    The proposed wide-field optical system has not been used yet. Described novel approach is based on the use of 1D "Lobster eye" optics in combination with Timepix X-ray detector in the energy range 3 - 40 keV. The proposed project includes theoretical study and a functional sample of the Timepix X-ray detector with multifoil wide-field X-ray "Lobster eye" optics. Using optics to focus X-rays on a detector is necessary in cases where the intensity of impinging X-ray radiation is below the sensitivity of the detector without optic. Generally this is the case of very low light phenomena, or e.g. monitoring astrophysical objects in space. Namely, such optical system could find applications in laboratory spectroscopy systems or in a rocket space experiment. Designed wide-field optical system combined with Timepix X-ray detector is described together with experimental results obtained during laboratory tests.

  8. Structural Characterization of Doped GaSb Single Crystals by X-ray Topography

    Energy Technology Data Exchange (ETDEWEB)

    Honnicke, M.G.; Mazzaro, I.; Manica, J.; Benine, E.; M da Costa, E.; Dedavid, B. A.; Cusatis, C.; Huang, X. R.

    2009-09-13

    We characterized GaSb single crystals containing different dopants (Al, Cd and Te), grown by the Czochralski method, by x-ray topography and high angular resolution x-ray diffraction. Lang topography revealed dislocations parallel and perpendicular to the crystal's surface. Double-crystal GaSb 333 x-ray topography shows dislocations and vertical stripes than can be associated with circular growth bands. We compared our high-angular resolution x-ray diffraction measurements (rocking curves) with the findings predicted by the dynamical theory of x-ray diffraction. These measurements show that our GaSb single crystals have a relative variation in the lattice parameter ({Delta}d/d) on the order of 10{sup -5}. This means that they can be used as electronic devices (detectors, for example) and as x-ray monochromators.

  9. Magnetic resonance imaging of the central nervous system. Comparison with X-ray CT

    Energy Technology Data Exchange (ETDEWEB)

    Kajima, Toshio; Kagawa, Yoshihiro; Katsuta, Shizutomo.

    1987-06-01

    Magnetic resonance imaging (MRI) and X-ray computed tomography (X-ray CT) have been performed in 169 consecutive patients with central nervous system diseases. The findings from the two methods were compared for the capacity to defect lesions. Magnetic resonance imaging was more sensitive than or equivalent to X-ray CT in detecting lesions - especially detecting. Arnold-Chiari malformation, syringomyelia, spinal cord injury, and pituitary adenoma - in 158 patients (94 %). In six patients (10 %), lesion detection was possible only by MRI. Magnetic resonance imaging was inferior to X-ray CT in 11 patients (7 %) in detecting calcified lesions, meningioma, and cavernous hemangioma. (Namekawa, K.).

  10. First X-ray fluorescence CT experimental results at the SSRF X-ray imaging beamline

    Institute of Scientific and Technical Information of China (English)

    DENG Biao; YANG Qun; XIE Hong-Lan; DU Guo-Hao; XIAO Wi-Qiao

    2011-01-01

    X-ray fluorescence CT is a non-destructive technique for detecting elemental composition and distribution inside a specimen. In this paper, the first experimental results of X-ray fluorescence CT obtained at the SSRF X-ray imaging beamline (BL13W1) are described. The test samples were investigated and the 2D elemental image was reconstructed using a filtered back-projection algorithm. In the sample the element Cd was observed. Up to now, the X-ray fluorescence CT could be carried out at the SSRF X-ray imaging beamline.

  11. Serial chest CT findings in interstitial lung disease associated with polymyositis-dermatomyositis

    Energy Technology Data Exchange (ETDEWEB)

    Bonnefoy, Olivier; Ferretti, Gilbert; Calaque, Olivier; Coulomb, Max; Begueret, Hugues; Beylot-Barry, Marie; Laurent, Francois E-mail: francois.laurent@chu-bordeaux.fr

    2004-03-01

    Objective: A retrospective study was carried out in two institutions to determine serial changes in the pattern, distribution, and extent of interstitial lung disease (ILD) associated with polymyositis (PM)-dermatomyositis (DM) using HRCT. Subjects and methods: Twenty patients with PM-DM and clinical suspicion of ILD who underwent at least two serial HRCT examinations were retrospectively evaluated by two readers. Patients were classified according to the dominant CT pattern which was correlated with clinical evolution and underlying histology when available (n=6). Results: Patients were classified into four groups according to the dominant pattern: ground-glass attenuation and reticulation (group 1, n=9); honeycombing (group 2, n=4); airspace consolidation (group 3, n=4), and normal or almost normal lung (group 4, n=3). Under medical treatment, serial HRCT showed that the extent of areas of ground-glass opacities (group 1) decreased in five patients, stabilized in two, and increased in two. Pathologic findings demonstrated usual interstitial pneumonia (UIP) in two cases and unspecified interstitial pneumonia in one. In group 2, extent of honeycombing increased in three cases and stabilized in one. In group 3, dramatic resolution of airspace consolidation occurred in three cases. Clinical deterioration with extensive consolidation at CT and diffuse alveolar damage (DAD) at histology occurred in one patient of each of the three previous groups. Lesions stayed invisible or progressed slightly in the fourth group. Conclusion: In ILD associated with PM-DM, clinical deterioration and DAD in the follow-up can be observed whatever the HRCT pattern. However, unfavorable evolution is constant when honeycombing is present at the initial CT.

  12. Various clinical application of phase contrast X-ray

    Science.gov (United States)

    Oh, Chilhwan; Park, Sangyong; Ha, Seunghan; Park, Gyuman; Lee, Gunwoo; Lee, Onseok; Je, Jungho

    2008-02-01

    In biomedical application study using phase contrast X-ray, both sample thickness or density and absorption difference are very important factors in aspects of contrast enhancement. We present experimental evidence that synchrotron hard X-ray are suitable for radiological imaging of biological samples down to the cellular level. We investigated the potential of refractive index radiology using un-monochromatized synchrotron hard X-rays for the imaging of cell and tissue in various diseases. Material had been adopted various medical field, such as apoE knockout mouse in cardiologic field, specimen from renal and prostatic carcinoma patient in urology, basal cell epithelioma in dermatology, brain tissue from autosy sample of pakinson's disease, artificially induced artilrtis tissue from rabbits and extracted tooth from patients of crack tooth syndrome. Formalin and paraffin fixed tissue blocks were cut in 3 mm thickness for the X-ray radiographic imaging. From adjacent areas, 4 μm thickness sections were also prepared for hematoxylin-eosin staining. Radiographic images of dissected tissues were obtained using the hard X-rays from the 7B2 beamline of the Pohang Light Source (PLS). The technique used for the study was the phase contrast images were compared with the optical microscopic images of corresponding histological slides. Radiographic images of various diseased tissues showed clear histological details of organelles in normal tissues. Most of cancerous lesions were well differentiated from adjacent normal tissues and detailed histological features of each tumor were clearly identified. Also normal microstructures were identifiable by the phase contrast imaging. Tissue in cancer or other disease showed clearly different findings from those of surrounding normal tissue. For the first time we successfully demonstrated that synchrotron hard X-rays can be used for radiological imaging of relatively thick tissue samples with great histological details.

  13. X-ray twinkles and Population III stars

    Science.gov (United States)

    Ricotti, Massimo

    2016-10-01

    Population III stars are typically massive stars of primordial composition forming at the centres of the first collapsed dark matter structures. Here we estimate the optimal X-ray emission in the early universe for promoting the formation of Population III stars. This is important in determining the number of dwarf galaxies formed before reionization and their fossils in the local universe, as well as the number of intermediate-mass seed black holes. A mean X-ray emission per source above the optimal level reduces the number of Population III stars because of the increased Jeans mass of the intergalactic medium, while a lower emission suppresses the formation rate of H2 preventing or delaying star formation in dark matter minihaloes above the Jeans mass. The build-up of the H2 dissociating background is slower than the X-ray background due to the shielding effect of resonant hydrogen Lyman lines. Hence, the nearly unavoidable X-ray emission from supernova remnants of Population III stars is sufficient to boost their number to few tens per comoving Mpc3 by redshift z ˜ 15. We find that there is a critical X-ray to ultraviolet energy ratio emitted per source that produces a universe where the number of Population III stars is largest: 400 per comoving Mpc3. This critical ratio is very close to the one provided by 20-40 M⊙ Population III stars exploding as hypernovae. High-mass X-ray binaries in dwarf galaxies are far less effective at increasing the number of Population III stars than normal supernova remnants, we thus conclude that supernovae drove the formation of Population III stars.

  14. Infrared Counterparts to Chandra X-Ray Sources in the Antennae

    CERN Document Server

    Clark, D M; Brandl, B R; Wilson, J C; Carson, J C; Henderson, C P; Hayward, T L; Barry, D J; Ptak, A F; Colbert, E J M

    2006-01-01

    We use deep J and Ks images of the Antennae (NGC 4038/9) obtained with WIRC on the Palomar 200-inch telescope, together with the Chandra X-ray source list of Zezas et al. (2002a), to search for IR counterparts to X-ray point sources. We establish an X-ray/IR astrometric frame tie with 0.5" rms residuals over a \\~4.3' field. We find 13 ``strong'' IR counterparts brighter than Ks = 17.8 mag and < 1.0" from X-ray sources, and an additional 6 ``possible'' IR counterparts between 1.0" and 1.5" from X-ray sources. The surface density of IR sources near the X-ray sources suggests only ~2 of the ``strong'' counterparts and ~3 of the ``possible'' counterparts are chance superpositions of unrelated objects. Comparing both strong and possible IR counterparts to our photometric study of ~220 Antennae, IR clusters, we find the IR counterparts to X-ray sources are \\~1.2 mag more luminous in Ks than average non-X-ray clusters. We also note that the X-ray/IR matches are concentrated in the spiral arms and ``overlap'' regi...

  15. Tracheal rupture caused by blunt chest trauma: radiological and clinical features

    Energy Technology Data Exchange (ETDEWEB)

    Kunisch-Hoppe, M.; Rauber, K.; Rau, W.S. [Dept. of Diagnostic Radiology, Justus Liebig Univ., Giessen (Germany); Hoppe, M. [Dept. of Diagnostic Radiology, University Hospital, Philipps University, Marburg (Germany); Popella, C. [Dept. of ENT, Justus Liebig University, Giessen (Germany)

    2000-03-01

    The aim of this study was to assess radiomorphologic and clinical features of tracheal rupture due to blunt chest trauma. From 1992 until 1998 the radiomorphologic and clinical key findings of all consecutive tracheal ruptures were retrospectively analyzed. The study included ten patients (7 men and 3 women; mean age 35 years); all had pneumothoraces which were persistent despite suction drainage. Seven patients developed a pneumomediastinum as well as a subcutaneous emphysema on conventional chest X-rays. In five patients, one major hint leading to the diagnosis was a cervical emphysema, discovered on the lateral cervical spine view. Contrast-media-enhanced thoracic CT was obtained in all ten cases and showed additional injuries (atelectasis n = 5; lung contusion n = 4; lung laceration n = 2; hematothorax n = 2 and hematomediastinum n = 4). The definite diagnosis of tracheal rupture was made by bronchoscopy, which was obtained in all patients. Tracheal rupture due to blunt chest trauma occurs rarely. Key findings were all provided by conventional chest X-ray. Tracheal rupture is suspected in front of a pneumothorax, a pneumomediastinum, or a subcutaneous emphysema on lateral cervical spine and chest films. Routine thoracic CT could also demonstrate these findings but could not confirm the definite diagnosis of an tracheal rupture except in one case; in the other 9 cases this was done by bronchoscopy. Thus, bronchoscopy should be mandatory in all suspicious cases of tracheal rupture and remains the gold standard. (orig.)

  16. X-ray in Zeta-Ori

    Science.gov (United States)

    López-García, M. A.; López-Santiago, J. L.; Albacete-Colombo, J. F.; De Castro, E.

    2013-05-01

    Nearby star-forming regions are ideal laboratories to study high-energy emission processes but they usually present high absorption what makes difficult to detect the stellar population inside the molecular complex. As young late-type stars show high X-ray emission and X-ray photons are little absorbed by interstellar material, X-ray dedicated surveys are an excellent tool to detect the low-mass stellar population in optically absorbed regions. In this work, we present a study of the star-forming region Zeta-Ori and its surroundings. We combine optical, infrared and X-ray data. Properties of the X-ray emiting plasma and infrared features of the young stellar objects detected in the XMM-Newton observation are determined. The southern part of the Orion B giant molecular cloud complex harbor other star forming regions, as NGC 2023 and NGC 2024, we use this regions to compare. We study the spectral energy distribution of X-ray sources. Combining these results with infrared, the X-ray sources are classified as class I, class II and class III objects. The X-ray spectrum and ligth curve of detected X-ray sources is analyzed to found flares. We use a extincion-independent index to select the stars with circumstellar disk, and study the relationship between the present of disk and the flare energy. The results are similar to others studies and we conclude that the coronal properties of class II and class III objects in this region do not differ significantly from each other and from stars of similar infrared class in the ONC.

  17. Frequency of x-ray examinations of neonates classified according to their birth weight in NICU

    Energy Technology Data Exchange (ETDEWEB)

    Ono, K.; Hada, M.; Mitarai, T.; Kato, Y. [Oita Prefectural Hospital, Department of Radiology, Oita (Japan); Akahane, K.; Kai, M.; Kusama, T. [Oita University of Nursing and Health Sciences, Oita (Japan)

    2000-05-01

    For neonates, red bone marrow is distributed in the whole body, and it is reported that cancer susceptibility to radiation may be higher than fetuses. However, there are few reports about the frequency of X-ray examination for neonates. To clarify the X-ray examination of neonates in intensive care unit, we investigated the actual frequency of mobile X-ray, CT and fluoroscopy. We followed the 306 infants who were admitted in and discharged from neonatal intensive care unit of Oita Prefecture Hospital between October 1 in 1998 and June 30 in 1999. The investigated items were types of radiograph, the number of mobile X-ray, and CT and fluoroscopy examination, the body weight at birth (BWAB), and the body weight at the day when X-ray examination was performed (BWXE). These were classified according to the BWAB. The relation between the frequency of X-ray examination and the high-risk-infant classification was examined. For mobile X-ray, the 1053 radiographs were performed, including 258 chest radiographs, 685 combined abdominal and chest radiographs, 52 abdominal radiographs, 37 wrist radiographs, 21 others radiographs. For CT, the 118 examinations was performed, including 116 head, 2 abdominal. For fluoroscopy, the 24 examinations were performed, including 13-air contrast enema, 5 gastroduodenal, 2 cystoradiogram, 1 urethrography, 1 intestine, 2 cavitas nasi and 152 abdominal radiographs. These showed that for less BWAB, more X-ray examinations were carried out. In the high-risk-infant classification, a lot of X-ray frequencies were observed for infants with extremely low BWAB. The infant with extremely low BWAB was accompanied with complication such as respiratory distress syndrome, chronic lung disease, and meconium disease. The histogram of the BWXE had two peaks; one at 600g-800g, another at 2100g-2500g. This study revealed the current frequency of X-rays examination in neonatal intensive care unit. We evaluated the dose to neonates in another paper of IRPA-10

  18. Two-dimensional x-ray diffraction

    CERN Document Server

    He, Bob B

    2009-01-01

    Written by one of the pioneers of 2D X-Ray Diffraction, this useful guide covers the fundamentals, experimental methods and applications of two-dimensional x-ray diffraction, including geometry convention, x-ray source and optics, two-dimensional detectors, diffraction data interpretation, and configurations for various applications, such as phase identification, texture, stress, microstructure analysis, crystallinity, thin film analysis and combinatorial screening. Experimental examples in materials research, pharmaceuticals, and forensics are also given. This presents a key resource to resea

  19. Soft X-Ray Laser Development

    Science.gov (United States)

    1989-10-01

    AND SUBTrI 5. FUNDING NUMBERS Soft X-ray Laser Development 61102F/2301/A8 L AUTHOR(S) ( Szymon Suckewer 7. PERFORMING ORGANIZATION NAME(S) AND ADORESS...REPORT Report of Progress on Soft X-ray Laser Development submitted to Air Force Office of Scientific Research by Acession For DT!C T.IB Princeton...x-ray laser development by Jaegl6 and coworkers 6, however the present work on aluminium plasmas pumped with a low energy Nd laser was primarily

  20. The Future of X-Ray Optics

    Science.gov (United States)

    Weisskopf, Martin C.

    2013-01-01

    The most important next step is the development of X-ray optics comparable to (or better than) Chandra in angular resolution that far exceed Chandra s effective area. Use the long delay to establish an adequately funded, competitive technology program along the lines I have recommended. Don't be diverted from this objective, except for Explorer-class missions. Progress in X-ray optics, with emphasis on the angular resolution, is central to the paradigm-shifting discoveries and the contributions of X-ray astronomy to multiwavelength astrophysics over the past 51 years.

  1. X-ray phase-contrast methods

    Energy Technology Data Exchange (ETDEWEB)

    Lider, V. V., E-mail: lider@ns.crys.ras.ru; Kovalchuk, M. V. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2013-11-15

    This review is devoted to a comparative description of the methods for forming X-ray phase-contrast images of weakly absorbing (phase) objects. These include the crystal interferometer method, the Talbot interferometer method, diffraction-enhanced X-ray imaging, and the in-line method. The potential of their practical application in various fields of science and technology is discussed. The publications on the development and optimization of X-ray phase-contrast methods and the experimental study of phase objects are analyzed.

  2. X-rays from Alpha Centauri

    Science.gov (United States)

    Nugent, J.; Garmire, G.

    1978-01-01

    HEAO 1 observations of soft X-ray emission from a point source in the vicinity of Alpha Cen are reported. The source, designated H1437-61, is tentatively identified with Alpha Cen, and an X-ray luminosity comparable to that of the sun in an active state is estimated. A temperature of about 500,000 K and an emission integral of 5 x 10 to the 50th per cu cm are obtained. Coronal emission is suggested as the X-ray-producing mechanism.

  3. Speckle Scanning Based X-ray Imaging

    CERN Document Server

    Berujon, Sebastien

    2015-01-01

    The X-ray near field speckle scanning concept is an approach recently introduced to obtain absorption, phase and darkfield images of a sample. In this paper, we demonstrate ways of recovering from a sample its ultra-small angle X-ray scattering distribution using numerical deconvolution, and the 2D phase gradient signal from random step scans, the latter being used to elude the flat field correction error. Each feature is explained theoretically and demonstrated experimentally at a synchrotron X-ray facility.

  4. A Burst Chasing X-ray Polarimeter

    Science.gov (United States)

    Hill, Joanne

    2007-01-01

    This viewgraph presentation reviews the rationale, design, and importance of an X-Ray Polarimeter. There is a brief discussion of Gamma Ray Bursts, followed by a review of the theories of Gamma-Ray Bursts Polarization. This leads to the question of "How do we measure the polarization?" and a discussion of the GRB x-ray emission, the photoelectric effect and photoelectric polarimetry. The requirements for the work, can only be approached using a gas detector. This leads to a discussion of a Micropattern Gas Polarimeter, and the Time-Projection Chamber (TPC) X-ray Polarimeter.

  5. Optics for coherent X-ray applications

    OpenAIRE

    2014-01-01

    Developments of X-ray optics for full utilization of diffraction-limited storage rings (DLSRs) are presented. The expected performance of DLSRs is introduced using the design parameters of SPring-8 II. To develop optical elements applicable to manipulation of coherent X-rays, advanced technologies on precise processing and metrology were invented. With propagation-based coherent X-rays at the 1 km beamline of SPring-8, a beryllium window fabricated with the physical-vapour-deposition method w...

  6. X-ray emission from the young brown dwarfs of the Taurus molecular cloud

    Science.gov (United States)

    Grosso, N.; Briggs, K. R.; Güdel, M.; Guieu, S.; Franciosini, E.; Palla, F.; Dougados, C.; Monin, J.-L.; Ménard, F.; Bouvier, J.; Audard, M.; Telleschi, A.

    2007-06-01

    Aims:We report the X-ray properties of young (~3 Myr) bona fide brown dwarfs of the Taurus Molecular Cloud (TMC). Methods: The XMM-Newton Extended Survey of the TMC (XEST) is a large program designed to systematically investigate the X-ray properties of young stellar/substellar objects in the TMC. In particular, the area surveyed by 15 XMM-Newton pointings (of which three are archival observations), supplemented with one archival Chandra observation, allows us to study 17 brown dwarfs with M spectral types. Results: Half of this sample (9 out of 17 brown dwarfs) is detected; 7 brown dwarfs are detected here for the first time in X-rays. We observed a flare from one brown dwarf. We confirm several previous findings on brown dwarf X-ray activity: a log-log relation between X-ray and bolometric luminosity for stars (with L* ≤ 10 L_⊙) and brown dwarfs detected in X-rays, which is consistent with a mean X-ray fractional luminosity =-3.5 ± 0.4; for the XEST brown dwarfs, the median of log(L_X/L_*) (including upper limits) is -4.0; a shallow log-log relation between X-ray fractional luminosity and mass; a log-log relation between X-ray fractional luminosity and effective temperature; a log-log relation between X-ray surface flux and effective temperature. We find no significant log-log correlation between the X-ray fractional luminosity and EW(Hα). Accreting and nonaccreting brown dwarfs have a similar X-ray fractional luminosity. The median X-ray fractional luminosity of nonaccreting brown dwarfs is about 4 times lower than the mean saturation value for rapidly rotating low-mass field stars. Our TMC brown dwarfs have higher X-ray fractional luminosity than brown dwarfs in the Chandra Orion Ultradeep Project. Conclusions: The X-ray fractional luminosity declines from low-mass stars to M-type brown dwarfs, and as a sample, the brown dwarfs are less efficient X-ray emitters than low-mass stars. We thus conclude that while the brown dwarf atmospheres observed here are

  7. A Comprehensive Archival Chandra Search for X-ray Emission from Ultracompact Dwarf Galaxies

    CERN Document Server

    Pandya, Viraj; Greene, Jenny E

    2016-01-01

    We present the first comprehensive archival study of the X-ray properties of ultracompact dwarf (UCD) galaxies, with the goal of identifying weakly-accreting central black holes in UCDs. Our study spans 578 UCDs distributed across thirteen different host systems, including clusters, groups, fossil groups, and isolated galaxies. Of the 336 spectroscopically-confirmed UCDs with usable archival Chandra imaging observations, 21 are X-ray-detected. Imposing a completeness limit of $L_X>2\\times10^{38}$ erg s$^{-1}$, the global X-ray detection fraction for the UCD population is $\\sim3\\%$. Of the 21 X-ray-detected UCDs, seven show evidence of long-term X-ray time variability on the order of months to years. X-ray-detected UCDs tend to be more compact than non-X-ray-detected UCDs, and we find tentative evidence that the X-ray detection fraction increases with surface luminosity density and global stellar velocity dispersion. The X-ray emission of UCDs is fully consistent with arising from a population of low-mass X-ra...

  8. On the black hole masses in ultra-luminous X-ray sources

    Science.gov (United States)

    Zhou, Xin-Lin

    2015-05-01

    Ultra-luminous X-ray sources (ULXs) are off-nuclear X-ray sources in nearby galaxies with X-ray luminosities ⩾ 1039 erg s-1. The measurement of the black hole (BH) masses of ULXs is a long-standing problem. Here we estimate BH masses in a sample of ULXs with XMM-Newton observations using two different mass indicators, the X-ray photon index and X-ray variability amplitude based on the correlations established for active galactic nuclei (AGNs). The BH masses estimated from the two methods are compared and discussed. We find that some extreme high-luminosity (LX > 5 ×1040 erg s-1) ULXs contain the BH of 104-105 M⊙ . The results from X-ray variability amplitude are in conflict with those from X-ray photon indices for ULXs with lower luminosities. This suggests that these ULXs generally accrete at rates different from those of X-ray luminous AGNs, or they have different power spectral densities of X-ray variability. We conclude that most of ULXs accrete at super-Eddington rate, thus harbor stellar-mass BH.

  9. A systematic search for X-ray cavities in galaxy clusters, groups, and elliptical galaxies

    CERN Document Server

    Shin, Jaejin; Mulchaey, John S

    2016-01-01

    We perform a comprehensive study of X-ray cavities using a large sample of X-ray targets selected from the Chandra archive. The sample is selected to cover a large dynamic range including galaxy clusters, groups, and individual galaxies. Using $\\beta$-modeling and unsharp masking techniques, we investigate the presence of X-ray cavities for 133 targets that have sufficient X-ray photons for analysis. We detect 148 X-ray cavities from 69 targets and measure their properties, including cavity size, angle, and distance from the center of the diffuse X-ray gas. We confirm the strong correlation between cavity size and distance from the X-ray center similar to previous studies (i.e., Birzan et al. 2004; Diehl et al. 2008; Dong et al. 2010). We find that the detection rates of X-ray cavities are similar among galaxy clusters, groups and individual galaxies, suggesting that the formation mechanism of X-ray cavities is independent of environment.

  10. X-ray Scattered Halo around IGR J17544-2619

    CERN Document Server

    Mao, Junjie; Zhang, Shuang-Nan

    2014-01-01

    X-ray photons coming from an X-ray point source not only arrive at the detector directly, but also can be strongly forward-scattered by the interstellar dust along the line of sight (LOS), leading to a detectable diffuse halo around the X-ray point source. The geometry of small angle X-ray scattering is straightforward, namely, the scattered photons travel longer paths and thus arrive later than the unscattered ones; thus the delay time of X-ray scattered halo photons can reveal information of the distances of the interstellar dust and the point source. Here we present a study of the X-ray scattered around IGR J17544-2619, which is one of the so-called supergiant fast X-ray transients. IGR J17544-2619 underwent a striking outburst when observed with Chandra on 2004 July 3, providing a near delta-function lightcurve. We find that the X-ray scattered halo around IGR J17544-2619 is produced by two interstellar dust clouds along the LOS. The one which is closer to the observer gives the X-ray scattered at larger ...

  11. On X-ray pulsations in β Cephei-type variables

    Science.gov (United States)

    Oskinova, L. M.; Todt, H.; Huenemoerder, D. P.; Hubrig, S.; Ignace, R.; Hamann, W.-R.; Balona, L.

    2015-05-01

    Context. β Cep-type variables are early B-type stars that are characterized by oscillations observable in their optical light curves. At least one β Cep-variable also shows periodic variability in X-rays. Aims: Here we study the X-ray light curves in a sample of β Cep-variables to investigate how common X-ray pulsations are for this type of stars. Methods: We searched the Chandra and XMM-Newton X-ray archives and selected stars that were observed by these telescopes for at least three optical pulsational periods. We retrieved and analyzed the X-ray data for κ Sco, β Cru, and α Vir. The X-ray light curves of these objects were studied to test for their variability and periodicity. Results: While there is a weak indication for X-ray variability in β Cru, we find no statistically significant evidence of X-ray pulsations in any of our sample stars. This might be due either to the insufficient data quality or to the physical lack of modulations. New, more sensitive observations should settle this question. The scientific results reported in this article are based on observations made by the Chandra and XMM-Newton X-ray Observatories, data obtained from the Chandra and XMM-Newton Data Archives, and observations made by the Chandra and XMM-Newton and published previously in cited articles.

  12. X-ray and optical studies of SAX J1808.4-3658 in quiescence

    NARCIS (Netherlands)

    C.O. Heinke; C.J. Deloye; P.G. Jonker; R. Wijnands; R.E. Taam

    2008-01-01

    We have observed the accreting millisecond X-ray pulsar SAX J1808.4-3658 (1808) in quiescence during two 50 ksec XMM-Newton observations, and acquired near-simultaneous photometry with Gemini South. We find 1808's X-ray spectrum to be hard, describable with an absorbed power-law of photon index 1.7-

  13. The neutron star soft X-ray transient 1H 1905+000 in quiescence

    NARCIS (Netherlands)

    Jonker, P.G.; Bassa, C.G.; Nelemans, G.; Juett, A.M.; Brown, E.F.; Chakrabarty, D.

    2006-01-01

    In this paper, we report on our analysis of a ~25ks. Chandra X-ray observation of the neutron star soft X-ray transient (SXT) 1H 1905+000 in quiescence. Furthermore, we discuss our findings of the analysis of optical photometric observations which we obtained using the Magellan telescope and photome

  14. X-ray Emission in Non-AGN Galaxies at z ~ 1

    CERN Document Server

    Chatterjee, Suchetana; Jeltema, Tesla; Myers, Adam D; Aird, James; Bundy, Kevin; Conselice, Christopher; Cooper, Michael; Laird, Elise; Nandra, Kirpal; Willmer, Christopher

    2015-01-01

    Using data from the DEEP2 galaxy redshift survey and the All Wavelength Extended Groth Strip International Survey we obtain stacked X-ray maps of galaxies at 0.7 1, we find no evidence that our results for X-ray scaling relations depend on optical color.

  15. The X-Ray, optical, and infrared counterpart to GRB 980703

    NARCIS (Netherlands)

    Vreeswijk, P.M.; Galama, T.J.; Owens, A.; Oosterbroek, T.; Geballe, T.R.; van Paradijs, J.; Groot, P.J.; Kouveliotou, C.; Wijers, R.A.M.J.

    1999-01-01

    We report on X-ray, optical, and infrared follow-up observations of GRB 980703. We detect a previously unknown X-ray source in the GRB error box; assuming a power-law decline, we find for its decay index alpha<-0.91 (3 sigma). We invoke host-galaxy extinction to match the observed spectral slope wit

  16. Catalogue of Galactic low-mass X-ray binaries (Liu+, 2007)

    NARCIS (Netherlands)

    Liu, Q.Z.; van Paradijs, J.A.; van den Heuvel, E.P.J.

    2007-01-01

    We present a new edition of the catalogue of the low-mass X-ray binaries in the Galaxy and the Magellanic Clouds. The catalogue contains source name(s), coordinates, finding chart, X-ray luminosity, system parameters, and stellar parameters of the components and other characteristic properties of 18

  17. Cumulative luminosity distributions of Supergiant Fast X-ray Transients in hard X-rays

    CERN Document Server

    Paizis, A

    2014-01-01

    We have analyzed in a systematic way about nine years of INTEGRAL data (17-100 keV) focusing on Supergiant Fast X-ray Transients (SFXTs) and three classical High Mass X-ray Binaries (HMXBs). Our approach has been twofold: image based analysis, sampled over a ~ks time frame to investigate the long-term properties of the sources, and lightcurve based analysis, sampled over a 100s time frame to seize the fast variability of each source during its ~ks activity. We find that while the prototypical SFXTs (IGR J17544-2619, XTE J1739-302 and SAX J1818.6-1703) are among the sources with the lowest ~ks based duty cycle ($<$1% activity over nine years of data), when studied at the 100s level, they are the ones with the highest detection percentage, meaning that, when active, they tend to have many bright short-term flares with respect to the other SFXTs. To investigate in a coherent and self consistent way all the available results within a physical scenario, we have extracted cumulative luminosity distributions for ...

  18. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy.

    Science.gov (United States)

    Miaja-Avila, L; O'Neil, G C; Uhlig, J; Cromer, C L; Dowell, M L; Jimenez, R; Hoover, A S; Silverman, K L; Ullom, J N

    2015-03-01

    We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ∼10(6) photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >10(7) laser pulses, we also present data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.

  19. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

    Directory of Open Access Journals (Sweden)

    L. Miaja-Avila

    2015-03-01

    Full Text Available We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ∼106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also present data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.

  20. Soft X-Ray Observations of a Complete Sample of X-Ray--selected BL Lacertae Objects

    Science.gov (United States)

    Perlman, Eric S.; Stocke, John T.; Wang, Q. Daniel; Morris, Simon L.

    1996-01-01

    We present the results of ROSAT PSPC observations of the X-ray selected BL Lacertae objects (XBLs) in the complete Einstein Extended Medium Sensitivity Survey (EM MS) sample. None of the objects is resolved in their respective PSPC images, but all are easily detected. All BL Lac objects in this sample are well-fitted by single power laws. Their X-ray spectra exhibit a variety of spectral slopes, with best-fit energy power-law spectral indices between α = 0.5-2.3. The PSPC spectra of this sample are slightly steeper than those typical of flat ratio-spectrum quasars. Because almost all of the individual PSPC spectral indices are equal to or slightly steeper than the overall optical to X-ray spectral indices for these same objects, we infer that BL Lac soft X-ray continua are dominated by steep-spectrum synchrotron radiation from a broad X-ray jet, rather than flat-spectrum inverse Compton radiation linked to the narrower radio/millimeter jet. The softness of the X-ray spectra of these XBLs revives the possibility proposed by Guilbert, Fabian, & McCray (1983) that BL Lac objects are lineless because the circumnuclear gas cannot be heated sufficiently to permit two stable gas phases, the cooler of which would comprise the broad emission-line clouds. Because unified schemes predict that hard self-Compton radiation is beamed only into a small solid angle in BL Lac objects, the steep-spectrum synchrotron tail controls the temperature of the circumnuclear gas at r ≤ 1018 cm and prevents broad-line cloud formation. We use these new ROSAT data to recalculate the X-ray luminosity function and cosmological evolution of the complete EMSS sample by determining accurate K-corrections for the sample and estimating the effects of variability and the possibility of incompleteness in the sample. Our analysis confirms that XBLs are evolving "negatively," opposite in sense to quasars, with Ve/Va = 0.331±0.060. The statistically significant difference between the values for X-ray

  1. The radiological findings of pulmonary paragonimiasis

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Byeung Suk; Song, Ho Yung; Im, Sun Kyun; Choi, Ki Chul [College of Medicine, Chunbuk National University, Jeonju (Korea, Republic of); Rhee, Hak Song [Presbyterian Medical Center, Jeonju (Korea, Republic of); Hong, Young Pyo [The Korean National Tuberculosis Association, Seoul (Korea, Republic of)

    1988-02-15

    Authors analysed chest X-ray findings in 36 cases of proven pulmonary paragonimiasis which sputum smears were positive for ova of Paragonimus Westermani from October 1978 to January 1987 at Chonbuk National University Hospital, PMC and Korean Institute of tuberculosis. The results are as follows: 1. Roentgenographic findings are cyst formation, pulmonary infiltration, fibrosis, pleural thickening, pleural effusion and pneumothorax. 2. The characteristic cystic shadows were observed in 19 cases (58%). They were multiple aggregated cysts surrounded with pericystic haziness and ranged in size from 1cm to 4cm in diameter. 3. Pulmonary infiltrations showed multiple, variable ill defined area of consolidation, predominantly in periphery of mid and lower lung field, which has migratory tendency. 4. Distribution of pulmonary lesions were bilateral (72%), mid lung fields (56%), and there were tendency of peripheral lung predominance. 5. 4 cases (11%) showed normal chest X-ray findings.

  2. X-ray induced optical reflectivity

    Directory of Open Access Journals (Sweden)

    Stephen M. Durbin

    2012-12-01

    Full Text Available The change in optical reflectivity induced by intense x-ray pulses can now be used to study ultrafast many body responses in solids in the femtosecond time domain. X-ray absorption creates photoelectrons and core level holes subsequently filled by Auger or fluorescence processes, and these excitations ultimately add conduction and valence band carriers that perturb optical reflectivity. Optical absorption associated with band filling and band gap narrowing is shown to explain the basic features found in recent measurements on an insulator (silicon nitride, Si3N4, a semiconductor (gallium arsenide, GaAs, and a metal (gold, Au, obtained with ∼100 fs x-ray pulses at 500-2000 eV and probed with 800 nm laser pulses. In particular GaAs exhibits an abrupt drop in reflectivity, persisting only for a time comparable to the x-ray excitation pulse duration, consistent with prompt band gap narrowing.

  3. X-ray source for mammography

    Science.gov (United States)

    Logan, Clinton M.

    1994-01-01

    An x-ray source utilizing anode material which shifts the output spectrum to higher energy and thereby obtains higher penetrating ability for screening mammography application, than the currently utilized anode material. The currently used anode material (molybdenum) produces an energy x-ray spectrum of 17.5/19.6 keV, which using the anode material of this invention (e.g. silver, rhodium, and tungsten) the x-ray spectrum would be in the 20-35 keV region. Thus, the anode material of this invention provides for imaging of breasts with higher than average x-ray opacity without increase of the radiation dose, and thus reduces the risk of induced breast cancer due to the radiation dose administered for mammograms.

  4. X-ray Emission from Solar Flares

    Indian Academy of Sciences (India)

    Rajmal Jain; Malini Aggarwal; Raghunandan Sharma

    2008-03-01

    Solar X-ray Spectrometer (SOXS), the first space-borne solar astronomy experiment of India was designed to improve our current understanding of X-ray emission from the Sun in general and solar flares in particular. SOXS mission is composed of two solid state detectors, viz., Si and CZT semiconductors capable of observing the full disk Sun in X-ray energy range of 4–56 keV. The X-ray spectra of solar flares obtained by the Si detector in the 4–25 keV range show evidence of Fe and Fe/Ni line emission and multi-thermal plasma. The evolution of the break energy point that separates the thermal and non-thermal processes reveals increase with increasing flare plasma temperature. Small scale flare activities observed by both the detectors are found to be suitable to heat the active region corona; however their location appears to be in the transition region.

  5. Experimental x-ray ghost imaging

    CERN Document Server

    Pelliccia, Daniele; Scheel, Mario; Cantelli, Valentina; Paganin, David M

    2016-01-01

    We report an experimental proof of principle for ghost imaging in the hard x-ray energy range. We used a synchrotron x-ray beam that was split using a thin crystal in Laue diffraction geometry. With an ultra-fast imaging camera, we were able to image x-rays generated by isolated electron bunches. At this time scale, the shot noise of the synchrotron emission process is measurable as speckles, leading to speckle correlation between the two beams. The integrated transmitted intensity from a sample located in the first beam was correlated with the spatially resolved intensity measured on the second, empty, beam to retrieve the shadow of the sample. The demonstration of ghost imaging with hard x-rays may open the way to protocols to reduce radiation damage in medical imaging and in non-destructive structural characterization using Free Electron Lasers.

  6. Astrophysics: Unexpected X-ray flares

    Science.gov (United States)

    Campana, Sergio

    2016-10-01

    Two sources of highly energetic flares have been discovered in archival X-ray data of 70 nearby galaxies. These flares have an undetermined origin and might represent previously unknown astrophysical phenomena. See Letter p.356

  7. Center for X-ray Optics (CXRO)

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for X-Ray Optics at Lawrence Berkeley National Laboratory works to further science and technology using short wavelength optical systems and techniques....

  8. Experimental X-Ray Ghost Imaging

    Science.gov (United States)

    Pelliccia, Daniele; Rack, Alexander; Scheel, Mario; Cantelli, Valentina; Paganin, David M.

    2016-09-01

    We report an experimental proof of principle for ghost imaging in the hard-x-ray energy range. We use a synchrotron x-ray beam that is split using a thin crystal in Laue diffraction geometry. With an ultrafast imaging camera, we are able to image x rays generated by isolated electron bunches. At this time scale, the shot noise of the synchrotron emission process is measurable as speckles, leading to speckle correlation between the two beams. The integrated transmitted intensity from a sample located in the first beam is correlated with the spatially resolved intensity measured in the second, empty, beam to retrieve the shadow of the sample. The demonstration of ghost imaging with hard x rays may open the way to protocols to reduce radiation damage in medical imaging and in nondestructive structural characterization using free electron lasers.

  9. Silicon Wafer X-ray Mirror Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this one year research project, we propose to do the following four tasks; (1) Design the silicon wafer X-ray mirror demo unit and develop a ray-tracing code to...

  10. Silicon Wafer X-ray Mirror Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this one year research project, we propose to do the following four tasks;(1) Design the silicon wafer X-ray mirror demo unit and develop a ray-tracing code to...

  11. Nonrelativistic quantum X-ray physics

    CERN Document Server

    Hau-Riege, Stefan P

    2015-01-01

    Providing a solid theoretical background in photon-matter interaction, Nonrelativistic Quantum X-Ray Physics enables readers to understand experiments performed at XFEL-facilities and x-ray synchrotrons. As a result, after reading this book, scientists and students will be able to outline and perform calculations of some important x-ray-matter interaction processes. Key features of the contents are that the scope reaches beyond the dipole approximation when necessary and that it includes short-pulse interactions. To aid the reader in this transition, some relevant examples are discussed in detail, while non-relativistic quantum electrodynamics help readers to obtain an in-depth understanding of the formalisms and processes. The text presupposes a basic (undergraduate-level) understanding of mechanics, electrodynamics, and quantum mechanics. However, more specialized concepts in these fields are introduced and the reader is directed to appropriate references. While primarily benefiting users of x-ray light-sou...

  12. X-ray crystallographic studies of metalloproteins.

    Science.gov (United States)

    Volbeda, Anne

    2014-01-01

    Many proteins require metals for their physiological function. In combination with spectroscopic characterizations, X-ray crystallography is a very powerful method to correlate the function of protein-bound metal sites with their structure. Due to their special X-ray scattering properties, specific metals may be located in metalloprotein structures and eventually used for phasing the diffracted X-rays by the method of Multi-wavelength Anomalous Dispersion (MAD). How this is done is the principle subject of this chapter. Attention is also given to the crystallographic characterization of different oxidation states of redox active metals and to the complication of structural changes that may be induced by X-ray irradiation of protein crystals.

  13. Demonstration of X-ray talbot interferometry

    CERN Document Server

    Momose, A; Kawamoto, S; Hamaishi, Y; Takai, K; Suzuki, Y

    2003-01-01

    First Talbot interferometry in the hard X-ray region was demonstrated using a pair of transmission gratings made by forming gold stripes on glass plates. By aligning the gratings on the optical axis of X-rays with a separation that caused the Talbot effect by the first grating, moire fringes were produced inclining one grating slightly against the other around the optical axis. A phase object placed in front of the first grating was detected by moire-fringe bending. Using the technique of phase-shifting interferometry, the differential phase corresponding to the phase object could also be measured. This result suggests that X-ray Talbot interferometry is a novel and simple method for phase-sensitive X-ray radiography. (author)

  14. Milli X-Ray Fluorescence Spectrometer

    Data.gov (United States)

    Federal Laboratory Consortium — The Eagle III Micro XRF unit is similar to a traditional XRF unit, with the primary difference being that the X-rays are focused by a polycapillary optic into a spot...

  15. The Need for X-Ray Spectroscopy

    Science.gov (United States)

    Winebarger, Amy R.; Cirtain, Jonathan; Kobayashi, Ken

    2011-01-01

    For over four decades, X-ray, EUV, and UV spectral observations have been used to measure physical properties of the solar atmosphere. During this time, there has been substantial improvement in the spectral, spatial, and temporal resolution of the observations for the EUV and UV wavelength ranges. At wavelengths below 100 Angstroms, however, observations of the solar corona with simultaneous spatial and spectral resolution are limited, and not since the late 1970's have spatially resolved solar X-ray spectra been measured. The soft-X-ray wavelength range is dominated by emission lines formed at high temperatures and provides diagnostics unavailable in any other wavelength range. In this presentation, we will discuss the important science questions that can be answered using spatially and spectrally resolved X-ray spectra.

  16. X-ray microtomography in biology

    CERN Document Server

    Mizutani, Ryuta

    2016-01-01

    Progress in high-resolution x-ray microtomography has provided us with a practical approach to determining three-dimensional (3D) structures of opaque samples at micrometer to submicrometer resolution. In this review, we give an introduction to hard x-ray microtomography and its application to the visualization of 3D structures of biological soft tissues. Practical aspects of sample preparation, handling, data collection, 3D reconstruction, and structure analysis are described. Furthermore, different sample contrasting methods are approached in detail. Examples of microtomographic studies are overviewed to present an outline of biological applications of x-ray microtomography. We also provide perspectives of biological microtomography as the convergence of sciences in x-ray optics, biology, and structural analysis.

  17. Capillary Optics generate stronger X-rays

    Science.gov (United States)

    1996-01-01

    NASA scientist, in the Space Sciences lab at Marshall, works with capillary optics that generate more intense X-rays than conventional sources. This capability is useful in studying the structure of important proteins.

  18. Chest MRI

    Science.gov (United States)

    Nuclear magnetic resonance - chest; Magnetic resonance imaging - chest; NMR - chest; MRI of the thorax; Thoracic MRI ... healthy enough to filter the contrast. During the MRI, the person who operates the machine will watch ...

  19. X-ray behaviour of Circinus X-1 - I: X-ray Dips as a diagnostic of periodic behaviour

    CERN Document Server

    Clarkson, W I

    2004-01-01

    We examine the periodic nature of detailed structure (particularly dips) in the RXTE/ASM lightcurve of Circinus X-1. The significant phase wandering of the X-ray maxima suggests their identification with the response on a viscous timescale of the accretion disk to perturbation. We find that the X-ray dips provide a more accurate system clock than the maxima, and thus use these as indicators of the times of periastron passage. We fit a quadratic ephemeris to these dips, and find its predictive power for the X-ray lightcurve to be superior to ephemerides based on the radio flares and the full archival X-ray lightcurve. Under the hypothesis that the dips are tracers of the mass transfer rate from the donor, we use their occurrence rate as a function of orbital phase to explore the (as yet unconstrained) nature of the donor. The high $\\dot{P}$ term in the ephemeris provides another piece of evidence that Cir X-1 is in a state of dynamical evolution, and thus is a very young post-supernova system. We further sugge...

  20. Parametric X-rays at FAST

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Tanaji [Fermilab

    2016-06-01

    We discuss the generation of parametric X-rays (PXR) in the photoinjector at the new FAST facility at Fermilab. Detailed calculations of the intensity spectrum, energy and angular widths and spectral brilliance with a diamond crystal are presented. We also report on expected results with PXR generated while the beam is channeling. The low emittance electron beam makes this facility a promising source for creating brilliant X-rays.

  1. Spectroscopy in X-ray astronomy

    Science.gov (United States)

    Andresen, R.

    1981-01-01

    Detailed features in cosmic X-ray sources and their associated temporal variation over a wide energy range were studied. Excess emission and absorption at approximately 6 to 7 kiloelectron volts in the spectra of supernova remnants, binary X-ray sources, and clusters of galaxies were observed. A gas scintillation proportional counter (GSPC) will be used as the detector system. In the gas scintillator the principal limitation is due to the statistics of the initial ionization process only.

  2. Globular cluster x-ray sources.

    Science.gov (United States)

    Pooley, David

    2010-04-20

    Globular clusters and x-ray astronomy have a long and fruitful history. Uhuru and OSO-7 revealed highly luminous (> 10(36) ergs(-1)) x-ray sources in globular clusters, and Einstein and ROSAT revealed a larger population of low-luminosity (luminosity sources were low-mass x-ray binaries in outburst and that they were orders of magnitude more abundant per unit mass in globular clusters than in the rest of the galaxy. However, the low-luminosity sources proved difficult to classify. Many ideas were put forth--low-mass x-ray binaries in quiescence (qLMXBs), cataclysmic variables (CVs), active main-sequence binaries (ABs), and millisecond pulsars (MSPs)--but secure identifications were scarce. In ROSAT observations of 55 clusters, about 25 low-luminosity sources were found. Chandra has now observed over 80 Galactic globular clusters, and these observations have revealed over 1,500 x-ray sources. The superb angular resolution has allowed for many counterpart identifications, providing clues to the nature of this population. It is a heterogeneous mix of qLMXBs, CVs, ABs, and MSPs, and it has been shown that the qLMXBs and CVs are both, in part, overabundant like the luminous LMXBs. The number of x-ray sources in a cluster correlates very well with its encounter frequency. This points to dynamical formation scenarios for the x-ray sources and shows them to be excellent tracers of the complicated internal dynamics. The relation between the encounter frequency and the number of x-ray sources has been used to suggest that we have misunderstood the dynamical states of globular clusters.

  3. Globular cluster x-ray sources

    Science.gov (United States)

    Pooley, David

    2010-01-01

    Globular clusters and x-ray astronomy have a long and fruitful history. Uhuru and OSO-7 revealed highly luminous (> 1036 ergs-1) x-ray sources in globular clusters, and Einstein and ROSAT revealed a larger population of low-luminosity (luminosity sources were low-mass x-ray binaries in outburst and that they were orders of magnitude more abundant per unit mass in globular clusters than in the rest of the galaxy. However, the low-luminosity sources proved difficult to classify. Many ideas were put forth—low-mass x-ray binaries in quiescence (qLMXBs), cataclysmic variables (CVs), active main-sequence binaries (ABs), and millisecond pulsars (MSPs)—but secure identifications were scarce. In ROSAT observations of 55 clusters, about 25 low-luminosity sources were found. Chandra has now observed over 80 Galactic globular clusters, and these observations have revealed over 1,500 x-ray sources. The superb angular resolution has allowed for many counterpart identifications, providing clues to the nature of this population. It is a heterogeneous mix of qLMXBs, CVs, ABs, and MSPs, and it has been shown that the qLMXBs and CVs are both, in part, overabundant like the luminous LMXBs. The number of x-ray sources in a cluster correlates very well with its encounter frequency. This points to dynamical formation scenarios for the x-ray sources and shows them to be excellent tracers of the complicated internal dynamics. The relation between the encounter frequency and the number of x-ray sources has been used to suggest that we have misunderstood the dynamical states of globular clusters. PMID:20404204

  4. Lacquer polishing of X-ray optics

    Science.gov (United States)

    Catura, R. C.; Joki, E. G.; Roethig, D. T.; Brookover, W. J.

    1987-01-01

    Techniques for polishing figured X-ray optics by a lacquer-coating process are described. This acrylic lacquer coating has been applied with an optical quality of an eighth-wave in red light and very effectively covers surface roughness with spatial wavelengths less than about 0.2 mm. Tungsten films have been deposited on the lacquer coatings to provide highly efficient X-ray reflectivity.

  5. X-ray scattering from dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    McSherry, D.J

    2000-09-01

    Dense plasmas were studied by probing them with kilovolt x-rays and measuring those scattered at various angles. The Laser-Produced x-ray source emitted Ti He alpha 4.75 keV x-rays. Two different plasma types were explored. The first was created by laser driven shocks on either side of a sample foil consisting of 2 micron Al layer, sandwiched between two 1 micron CH layers. We have observed a peak in the x-ray scattering cross section, indicating diffraction from the plasma. However, the experimentally inferred plasma density, broadly speaking, did not always agree with the hydrodynamic simulation MEDX (A modified version of MEDUSA). The second plasma type that we studied was created by soft x-ray heating on either side of a sample foil, this time consisting of 1 micron layer of Al, sandwiched between two 0.2 micron CH layers. Two foil targets, each consisting of a 0.1 micron thick Au foil mounted on 1 micron of CH, where placed 4 mm from the sample foil. The soft x-rays where produced by laser irradiating these two foil targets. We found that, 0.5 ns after the peak of the laser heating pulses, the measured cross sections more closely matched those simulated using the Thomas Fermi model than the Inferno model. Later in time, at 2 ns, the plasma is approaching a weakly coupled state. This is the first time x-ray scattering cross sections have been measured from dense plasmas generated by radiatively heating both sides of the sample. Moreover, these are absolute values typically within a factor of two of expectation for early x-ray probe times. (author)

  6. X-ray induced optical reflectivity

    OpenAIRE

    2012-01-01

    The change in optical reflectivity induced by intense x-ray pulses can now be used to study ultrafast many body responses in solids in the femtosecond time domain. X-ray absorption creates photoelectrons and core level holes subsequently filled by Auger or fluorescence processes, and these excitations ultimately add conduction and valence band carriers that perturb optical reflectivity. Optical absorption associated with band filling and band gap narrowing is shown to explain the basic featur...

  7. X- rays and matter- the basic interactions

    DEFF Research Database (Denmark)

    Als-Nielsen, Jens

    2008-01-01

    In this introductory article we attempt to provide the theoretical basis for developing the interaction between X-rays and matter, so that one can unravel properties of matter by interpretation of X-ray experiments on samples. We emphasize that we are dealing with the basics, which means that we ...... this article: J. Als-Nielsen, C. R. Physique 9 (2008). Udgivelsesdato: 18 April...

  8. Capacitor discharges, magnetohydrodynamics, X-rays, ultrasonics

    CERN Document Server

    Früngel, Frank B A

    1965-01-01

    High Speed Pulse Technology, Volume 1: Capacitor Discharges - Magnetohydrodynamics - X-Rays - Ultrasonics deals with the theoretical and engineering problems that arise in the capacitor discharge technique.This book discusses the characteristics of dielectric material, symmetrical switch tubes with mercury filling, and compensation conductor forms. The transformed discharge for highest current peaks, ignition transformer for internal combustion engines, and X-ray irradiation of subjects in mechanical motion are also elaborated. This text likewise covers the transformed capacitor discharge in w

  9. X-ray tube output based calculation of patient entrance surface dose: validation of the method

    Energy Technology Data Exchange (ETDEWEB)

    Harju, O.; Toivonen, M.; Tapiovaara, M.; Parviainen, T. [Radiation and Nuclear Safety Authority, Helsinki (Finland)

    2003-06-01

    X-ray departments need methods to monitor the doses delivered to the patients in order to be able to compare their dose level to established reference levels. For this purpose, patient dose per radiograph is described in terms of the entrance surface dose (ESD) or dose-area product (DAP). The actual measurement is often made by using a DAP-meter or thermoluminescent dosimeters (TLD). The third possibility, the calculation of ESD from the examination technique factors, is likely to be a common method for x-ray departments that do not have the other methods at their disposal or for examinations where the dose may be too low to be measured by the other means (e.g. chest radiography). We have developed a program for the determination of ESD by the calculation method and analysed the accuracy that can be achieved by this indirect method. The program calculates the ESD from the current time product, x-ray tube voltage, beam filtration and focus- to-skin distance (FSD). Additionally, for calibrating the dose calculation method and thereby improving the accuracy of the calculation, the x-ray tube output should be measured for at least one x-ray tube voltage value in each x-ray unit. The aim of the present work is to point out the restrictions of the method and details of its practical application. The first experiences from the use of the method will be summarised. (orig.)

  10. Elliptical X-Ray Spot Measurement

    CERN Document Server

    Richardson, R A; Weir, J T; Richardson, Roger A.; Sampayan, Stephen; Weir, John T.

    2000-01-01

    The so-called roll bar measurement uses a heavy metal material, optically thick to x-rays, to form a shadow of the x-ray origination spot. This spot is where an energetic electron beam interacts with a high Z target. The material (the "roll bar") is slightly curved to avoid alignment problems. The roll bar is constructed and positioned so that the x-rays are shadowed in the horizontal and vertical directions, so information is obtained in two dimensions. If a beam profile is assumed (or measured by other means), the equivalent x-ray spot size can be calculated from the x-ray shadow cast by the roll bar. Thus the ellipticity of the beam can be calculated, assuming the ellipse of the x-ray spot is aligned with the roll bar. The data is recorded using a scintillator and gated camera. Data will be presented from measurements using the ETA II induction LINAC. The accuracy of the measurement is checked using small elliptical targets.

  11. Optics Developments for X-Ray Astronomy

    Science.gov (United States)

    Ramsey, Brian

    2014-01-01

    X-ray optics has revolutionized x-ray astronomy. The degree of background suppression that these afford, have led to a tremendous increase in sensitivity. The current Chandra observatory has the same collecting area (approx. 10(exp 3)sq cm) as the non-imaging UHURU observatory, the first x-ray observatory which launched in 1970, but has 5 orders of magnitude more sensitivity due to its focusing optics. In addition, its 0.5 arcsec angular resolution has revealed a wealth of structure in many cosmic x-ray sources. The Chandra observatory achieved its resolution by using relatively thick pieces of Zerodur glass, which were meticulously figured and polished to form the four-shell nested array. The resulting optical assembly weighed around 1600 kg, and cost approximately $0.5B. The challenge for future x-ray astronomy missions is to greatly increase the collecting area (by one or more orders of magnitude) while maintaining high angular resolution, and all within realistic mass and budget constraints. A review of the current status of US optics for x-ray astronomy will be provided along with the challenges for future developments.

  12. The X-ray imager on AXO

    Science.gov (United States)

    Budtz-Jørgensen, C.; Kuvvetli, I.; Westergaard, N. J.; Jonasson, P.; Reglero, V.; Eyles, C.

    2001-02-01

    DSRI has initiated a development program of CZT X-ray and gamma-ray detectors employing strip readout techniques. A dramatic improvement of the energy response was found operating the detectors as the so-called drift detectors. For the electronic readout, modern ASIC chips were investigated. Modular design and the low-power electronics will make large area detectors using the drift strip method feasible. The performance of a prototype CZT system will be presented and discussed. One such detector system has been proposed for future space missions: the X-Ray Imager (XRI) on the Atmospheric X-ray Observatory (AXO), which is a mission proposed to the Danish Small Satellite Program and is dedicated to observations of X-ray generating processes in the Earth's atmosphere. Of special interest will be simultaneous optical and X-ray observations of sprites that are flashes appearing directly above an active thunderstorm system. Additional objective is a detailed mapping of the auroral X-ray and optical emission. XRI comprises a coded mask and a 20×40 cm 2 CZT detector array covering an energy range from 5 to 200 keV.

  13. Coherence in X-ray physics.

    Science.gov (United States)

    Lengeler, B

    2001-06-01

    Highly brilliant synchrotron radiation sources have opened up the possibility of using coherent X-rays in spectroscopy and imaging. Coherent X-rays are characterized by a large lateral coherence length. Speckle spectroscopy is extended to hard X-rays, improving the resolution to the nm range. It has become possible to image opaque objects in phase contrast with a sensitivity far superior to imaging in absorption contrast. All the currently available X-ray sources are chaotic sources. Their characterization in terms of coherence functions of the first and second order is introduced. The concept of coherence volume, defined in quantum optics terms, is generalized for scattering experiments. When the illuminated sample volume is smaller than the coherence volume, the individuality of the defect arrangement in a sample shows up as speckle in the scattered intensity. Otherwise, a configurational average washes out the speckle and only diffuse scattering and possibly Bragg reflections will survive. The loss of interference due to the finite detection time, to the finite detector pixel size and to uncontrolled degrees of freedom in the sample is discussed at length. A comparison between X-ray scattering, neutron scattering and mesoscopic electron transport is given. A few examples illustrate the possibilities of coherent X-rays for imaging and intensity correlation spectroscopy.

  14. X-ray Emission of Hollow Atoms

    Institute of Scientific and Technical Information of China (English)

    ZhaoYongtao; XiaoGuoqing; ZhangXiaoan; YangZhihu; ChenXimeng; ZhangYanping

    2003-01-01

    We have systematically investigated the X-rays emission of hollow atoms (HA) which formed in the interaction of highly charged ions with a variety of solid surfaces at the atomic physics experimental setup of IMP. The X-ray spectra were measured by Si(Li) detectors with effective energy ranging from 1 keV to 60 keV. The results show that, the X-ray emission from the formed HA is closely correlated with the charge state of the projectile ions, and weakly correlated with the velocity of the projectile ions. For example, it was found that when Ar18+ ions interact with Be-target, the yield of K X-ray with character energy of 3.0 keV is 7.2×10-3 per ion, which is two times and 5 order of magnitude higher than those in the interactions of Ar17+ and Ar16+ ions respectively. When Ar15+ ions interact with the same targets, the Argon K X-ray would be too feeble to be detected. The X-ray yield with single ion in this experiment can be represented by the following equation,

  15. The SAS-3 X-ray observatory

    Science.gov (United States)

    Mayer, W. F.

    1975-01-01

    The experiment section of the Small Astronomy Satellite-3 (SAS-3) launched in May 1975 is an X-ray observatory intended to determine the location of bright X-ray sources to an accuracy of 15 arc-seconds; to study a selected set of sources over a wide energy range, from 0.1 to 55 keV, while performing very specific measurements of the spectra and time variability of known X-ray sources; and to monitor the sky continuously for X-ray novae, flares, and unexpected phenomena. The improvements in SAS-3 spacecraft include a clock accurate to 1 part in 10 billion, rotatable solar panels, a programmable data format, and improved nutation damper, a delayed command system, improved magnetic trim and azimuth control systems. These improvements enable SAS-3 to perform three-axis stabilized observations of any point on the celestial sphere at any time of the year. The description of the experiment section and the SAS-3 operation is followed by a synopsis of scientific results obtained from the observations of X-ray sources, such as Vela X-1 (supposed to be an accreting neutron star), a transient source of hard X-ray (less than 36 min in duration) detected by SAS-3, the Crab Nebula pulsar, the Perseus cluster of galaxies, and the Vela supernova remnant.

  16. Optics for coherent X-ray applications

    Energy Technology Data Exchange (ETDEWEB)

    Yabashi, Makina, E-mail: yabashi@spring8.or.jp [RIKEN SPring-8 Center, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Tono, Kensuke [Japan Synchrotron Radiation Research Institute (JASRI), Kouto 1-1-1, Sayo, Hyogo 679-5198 (Japan); Mimura, Hidekazu [The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8656 (Japan); Matsuyama, Satoshi; Yamauchi, Kazuto [Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Tanaka, Takashi; Tanaka, Hitoshi; Tamasaku, Kenji [RIKEN SPring-8 Center, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan); Ohashi, Haruhiko; Goto, Shunji [Japan Synchrotron Radiation Research Institute (JASRI), Kouto 1-1-1, Sayo, Hyogo 679-5198 (Japan); Ishikawa, Tetsuya [RIKEN SPring-8 Center, Kouto 1-1-1, Sayo, Hyogo 679-5148 (Japan)

    2014-08-27

    Developments of optics for coherent X-ray applications and their role in diffraction-limited storage rings are described. Developments of X-ray optics for full utilization of diffraction-limited storage rings (DLSRs) are presented. The expected performance of DLSRs is introduced using the design parameters of SPring-8 II. To develop optical elements applicable to manipulation of coherent X-rays, advanced technologies on precise processing and metrology were invented. With propagation-based coherent X-rays at the 1 km beamline of SPring-8, a beryllium window fabricated with the physical-vapour-deposition method was found to have ideal speckle-free properties. The elastic emission machining method was utilized for developing reflective mirrors without distortion of the wavefronts. The method was further applied to production of diffraction-limited focusing mirrors generating the smallest spot size in the sub-10 nm regime. To enable production of ultra-intense nanobeams at DLSRs, a low-vibration cooling system for a high-heat-load monochromator and advanced diagnostic systems to characterize X-ray beam properties precisely were developed. Finally, new experimental schemes for combinative nano-analysis and spectroscopy realised with novel X-ray optics are discussed.

  17. Anti-correlated hard X-ray time lags in Galactic black hole sources

    CERN Document Server

    Sriram, K; Pendharkar, J K; Rao, A R; Pendharkar, Jayant K.

    2007-01-01

    We investigate the accretion disk geometry in Galactic black hole sources by measuring the time delay between soft and hard X-ray emissions. Similar to the recent discoveries of anti-correlated hard X-ray time lags in Cyg X-3 and GRS 1915+105, we find that the hard X-rays are anti-correlated with soft X-rays with a significant lag in another source: XTE J1550-564. We also find the existence of pivoting in the model independent X-ray spectrum during these observations. We investigate time-resolved X-ray spectral parameters and find that the variation in these parameters is consistent with the idea of a truncated accretion disk. The QPO frequency, which is a measure of the size of truncated accretion disk, too changes indicating that the geometric size of the hard X-ray emitting region changes along with the spectral pivoting and soft X-ray flux. Similar kind of delay is also noticed in 4U 1630-47.

  18. Inverse Compton X-ray signature of AGN feedback

    Science.gov (United States)

    Bourne, Martin A.; Nayakshin, Sergei

    2013-12-01

    Bright AGN frequently show ultrafast outflows (UFOs) with outflow velocities vout ˜ 0.1c. These outflows may be the source of AGN feedback on their host galaxies sought by galaxy formation modellers. The exact effect of the outflows on the ambient galaxy gas strongly depends on whether the shocked UFOs cool rapidly or not. This in turn depends on whether the shocked electrons share the same temperature as ions (one-temperature regime, 1T) or decouple (2T), as has been recently suggested. Here we calculate the inverse Compton spectrum emitted by such shocks, finding a broad feature potentially detectable either in mid-to-high energy X-rays (1T case) or only in the soft X-rays (2T). We argue that current observations of AGN do not seem to show evidence for the 1T component. The limits on the 2T emission are far weaker, and in fact it is possible that the observed soft X-ray excess of AGN is partially or fully due to the 2T shock emission. This suggests that UFOs are in the energy-driven regime outside the central few pc, and must pump considerable amounts of not only momentum but also energy into the ambient gas. We encourage X-ray observers to look for the inverse Compton components calculated here in order to constrain AGN feedback models further.

  19. Dark Matter Detection with Hard X-ray Telescopes

    CERN Document Server

    Jeltema, Tesla E

    2011-01-01

    We analyze the impact of future hard X-ray observations on the search for indirect signatures of particle dark matter in large extragalactic systems such as nearby clusters or groups of galaxies. We argue that the hard X-ray energy band falls squarely at the peak of the inverse Compton emission from electrons and positrons produced by dark matter annihilation or decay for a large class of dark matter models. Specifically, the most promising are low-mass models with a hard electron-positron annihilation final state spectrum and intermediate-mass models with a soft electron-positron spectrum. We find that constraints on dark matter models similar to the current constraints from the Fermi Gamma-Ray Space Telescope will be close to the limit of the sensitivity of the near-term hard X-ray telescopes NuSTAR and ASTRO-H for relatively long observations, but an instrument similar to the Wide Field Imager proposed for the International X-ray Observatory would allow significant gains to be made. In the future, the abil...

  20. Development of microchannel plate x-ray optics

    Science.gov (United States)

    Kaaret, Philip

    1995-01-01

    The goal of this research program was to develop a novel technique for focusing x-rays based on the optical system of a lobster's eye. A lobster eye employs many closely packed reflecting surfaces arranged within a spherical or cylindrical shell. These optics have two unique properties: they have unlimited fields of view and can be manufactured via replication of identical structures. Because the angular resolution is given by the ratio of the size of the individual optical elements to the focal length, optical elements with size on the order of one hundred microns are required to achieve good angular resolution with a compact telescope. We employed anisotropic etching of single crystal silicon wafers for the fabrication of micron-scale optical elements. This technique, commonly referred to as silicon micromachining, is based on silicon fabrication techniques developed by the microelectronics industry. We have succeeded in producing silicon lenses with a geometry suitable for a 1-d focusing x-ray optics. These lenses have an aspect ratio (40:1) suitable for x-ray reflection and have very good optical surface alignment. We have developed a number of process refinements which improved the quality of the lens geometry and the repeatability of the etch process. In addition to the silicon fabrication, an x-ray beam line was constructed at Columbia for testing the optics. Most recently, we have done several experiments to find the fundamental limits that the anisotropic etch process placed on the etched surface roughness.

  1. X-ray refractive index of laser-dressed atoms

    CERN Document Server

    Buth, Christian

    2008-01-01

    We investigated the complex index of refraction in the x-ray regime of atoms in laser light. The laser (intensity up to 10^13 W/cm^2, 800nm) modifies the atomic states but, by assumption, does not excite or ionize the atoms in their electronic ground state. Using quantum electrodynamics, we devise an ab initio theory to calculate the dynamic dipole polarizability and the photoabsorption cross section, which are subsequently used to determine the real and imaginary part, respectively, of the refractive index. The interaction with the laser is treated nonperturbatively; the x-ray interaction is described in terms of a one-photon process. We numerically solve the resolvents involved using a single-vector Lanczos algorithm. Finally, we formulate rate equations to copropagate a laser and an x-ray pulse through a gas cell. Our theory is applied to argon. We study the x-ray polarizability and absorption near the argon K edge over a large range of dressing-laser intensities. We find electromagnetically induced transp...

  2. X-RAY SOURCES IN THE DWARF SPHEROIDAL GALAXY DRACO

    Energy Technology Data Exchange (ETDEWEB)

    Sonbas, E. [University of Adiyaman, Department of Physics, 02040 Adiyaman (Turkey); Rangelov, B.; Kargaltsev, O.; Dhuga, K. S.; Hare, J.; Volkov, I., E-mail: edasonbas@yahoo.com [Department of Physics, The George Washington University, Washington, DC 20052 (United States)

    2016-04-10

    We present the spectral analysis of an 87 ks XMM-Newton observation of Draco, a nearby dwarf spheroidal galaxy. Of the approximately 35 robust X-ray source detections, we focus our attention on the brightest of these sources, for which we report X-ray and multiwavelength parameters. While most of the sources exhibit properties consistent with active galactic nuclei, few of them possess the characteristics of low-mass X-ray binaries (LMXBs) and cataclysmic variable (CVs). Our analysis places constraints on the population of X-ray sources with L{sub X} > 3 × 10{sup 33} erg s{sup −1} in Draco, suggesting that there are no actively accreting black hole and neutron star binaries. However, we find four sources that could be quiescent state LMXBs/CVs associated with Draco. We also place constraints on the central black hole luminosity and on a dark matter decay signal around 3.5 keV.

  3. Stellar X-ray sources in the Chandra COSMOS survey

    CERN Document Server

    Wright, Nicholas J; Civano, Francesca

    2010-01-01

    We present an analysis of the X-ray properties of a sample of solar- and late-type field stars identified in the Chandra Cosmic Evolution Survey (COSMOS), a deep (160ks) and wide (0.9 deg2) extragalactic survey. The sample of 60 sources was identified using both morphological and photometric star/galaxy separation methods. We determine X-ray count rates, extract spectra and light curves and perform spectral fits to determine fluxes and plasma temperatures. Complementary optical and near-IR photometry is also presented and combined with spectroscopy for 48 of the sources to determine spectral types and distances for the sample. We find distances ranging from 30pc to ~12kpc, including a number of the most distant and highly active stellar X-ray sources ever detected. This stellar sample extends the known coverage of the L_X-distance plane to greater distances and higher luminosities, but we do not detect as many intrinsically faint X-ray sources compared to previous surveys. Overall the sample is typically more...

  4. White Dwarf Mass Estimation with X-ray Spectroscopy

    Science.gov (United States)

    Hayashi, T.

    2017-03-01

    I present X-ray spectral modeling of intermediate polars (IPs) and its application to Suzaku satellite data. The intrinsic thermal X-rays are modeled by integrating the plasma emissions of various temperatures in the post-shock accretion column (PSAC). The physical quantity distributions for the thermal spectral model is calculated from quasi-one-dimensional hydrodynamics. The PSAC calculation includes especially the dipolar geometry and variation of the specific accretion rate. The X-ray reflection from the white dwarf (WD) is modeled by a Monte Carlo simulation. In this simulation, the PSAC irradiates a cool, neutral and spherical WD with the various thermal spectra from the corresponding positions in the PSAC according to the thermal spectral model. The coherent and incoherent scattering, the photoelectric absorption, and Kα and Kβ re-emission of iron and nickel are taken into account for the photons arriving at the WD. The constructed X-ray spectral model is applied to EX Hya and V1223 Sgr, finding 0.65+0.11 –0.12 M⊙ and 0.91+0.08–0.03 M⊙, respectively. Their specific accretion rates are estimated at 0.069+0.33–0.045 g cm–2 s-1 and > 2 g cm–2 s-1, respectively, while the reflecting angles are 78.0–1.6+1.4 deg and 66.2+2.5–2.3 deg, respectively.

  5. X-ray states of redback millisecond pulsars

    Energy Technology Data Exchange (ETDEWEB)

    Linares, M. [Instituto de Astrofísica de Canarias, c/Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain)

    2014-11-01

    Compact binary millisecond pulsars with main-sequence donors, often referred to as 'redbacks', constitute the long-sought link between low-mass X-ray binaries and millisecond radio pulsars and offer a unique probe of the interaction between pulsar winds and accretion flows. We present a systematic study of eight nearby redbacks, using more than 100 observations obtained with Swift's X-ray Telescope. We distinguish between three main states: pulsar, disk, and outburst states. We find X-ray mode switching in the disk state of PSR J1023+0038 and XSS J12270-4859, similar to what was found in the other redback that showed evidence for accretion: rapid, recurrent changes in X-ray luminosity (0.5-10 keV, L {sub X}), between (6-9) × 10{sup 32} erg s{sup –1} (disk-passive state) and (3-5) × 10{sup 33} erg s{sup –1} (disk-active state). This strongly suggests that mode switching—which has not been observed in quiescent low-mass X-ray binaries—is universal among redback millisecond pulsars in the disk state. We briefly explore the implications for accretion disk truncation and find that the inferred magnetospheric radius in the disk state of PSR J1023+0038 and XSS J12270-4859 lies outside the light cylinder. Finally, we note that all three redbacks that have developed accretion disks have relatively high L {sub X} in the pulsar state (>10{sup 32} erg s{sup –1}).

  6. Soft X-ray Properties of Ultraluminous IRAS Galaxies

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We report on the results of cross-correlation of a sample of 903 Ultra luminous IRAS galaxies (ULIRGs) with the ROSAT-All Sky Survey Bright Source Catalogue and the ROSAT archived pointing observations. The sample of ULIRGs has been compiled from the recently released PSCz redshift survey. In total, 35 ULIRGs are securely detected by the ROSAT All-Sky Survey and pointing observa tions, five of which are blazars. The statistical properties of these sources in the soft X-ray band are determined and compared with their properties in other wavebands. We find that the ratio of the soft X-ray to the far-infrared flux spans about five orders of magnitude and reaches values of about unity. This ratio is a good indi cator of the main energy source of ULIRGs. Those with soft X-ray to far-infrared flux exceeding 0.01 are probably powered by accretion onto central supermassive black holes while those with ratios smaller than 0.001 are probably powered by starbursts or other heating processes, or are Compton thick sources. Some ULIRGs have energy contributions from both. This ratio is low for most ULIRGs and hy perluminous infrared galaxies, which explains their low detection rate by ROSAT and ASCA. We also find that some ULIRGs have a similar soft X-ray luminosity vs. temperature relation to that for groups of galaxies and elliptical galaxies, suggest ing a common origin of these systems. Our study also reveals a tight correlation between the hardness ratio and the soft X-ray luminosity for Seyfert ls/QSOs.

  7. Thin-section chest CT findings of primary Sjoegren's syndrome: correlation with pulmonary function

    Energy Technology Data Exchange (ETDEWEB)

    Taouli, Bachir; Mourey, Isabelle [Department of Radiology, Universite Pierre et Marie Curie, Paris (France); Brauner, Michel W.; Lemouchi, Djamel [Department of Radiology, Universite Paris XIII, Bobigny (France); Grenier, Philippe A. [Department of Radiology, Universite Pierre et Marie Curie, Paris (France); Institut National de la Sante et de la Recherche Medicale, Universite Pierre et Marie Curie, Paris (France)

    2002-06-01

    The purpose of this study was to describe thin-section CT findings of lung involvement in patients with primary Sjoegren's syndrome (PSS), and to correlate them with pulmonary function tests (PFT). The chest thin-section CT examinations of 35 patients with proven diagnosis of PSS and respiratory symptoms were retrospectively assessed by two observers, in a first step independently with interobserver evaluation, and in a second step in consensus. The extent of the most frequent CT findings was scored. Correlation was made with PFT in 31 of these patients. Three main CT patterns were identified with good interobserver agreement (kappa coefficient 0.71): 19 of 35 (54%) large and/or small airways disease; 7 of 35 (20%) interstitial lung fibrosis (ILF); and 5 of 35 (14%) suggestive of lymphocytic interstitial pneumonia (LIP). The CT scans were normal in 2 patients (6%) and showed only dilatation of pulmonary vessels due to pulmonary arterial hypertension in two others (6%). Airway disease patients had predominantly obstructive profiles (mean FEV{sub 1}/FVC ratio 69.7{+-}12.7%, mean MEF{sub 25} 50.1{+-}22.9%), whereas patients with ILF and LIP had predominantly restrictive profiles and/or a decreased diffusing lung capacity (mean TLC 87.0{+-}26.0 and 64.6{+-}18.6%, mean DL{sub CO} 57.4{+-}21.2 and 52.0{+-}8.0%). Significant correlation (p<0.01) was found between the scores of ground-glass attenuation and TLC (r=-0.84) and DL{sub CO} (r=-0.70) and between the score of air trapping and FEV1 (r=-1.0). In patients with PSS and respiratory symptoms, thin-section CT may provide characterization of lung involvement which correlates with pulmonary function. (orig.)

  8. Echo Emission From Dust Scattering and X-Ray Afterglows of Gamma-Ray Bursts

    CERN Document Server

    Shao, L; Mirabal, N

    2007-01-01

    We investigate the effect of X-ray echo emission in gamma-ray bursts (GRBs). We find that the echo emission can provide an alternative way of understanding X-ray shallow decays and jet breaks. In particular, a shallow decay followed by a "normal" decay and a further rapid decay of X-ray afterglows can be together explained as being due to the echo from prompt X-ray emission scattered by dust grains in a massive wind bubble around a GRB progenitor. We also introduce an extra temporal break in the X-ray echo emission. By fitting the afterglow light curves, we can measure the locations of the massive wind bubbles, which will bring us closer to finding the mass loss rate, wind velocity, and the age of the progenitors prior to the GRB explosions.

  9. 4. Preliminary Findings of a Prospective Study of FDG-PET in Patients with Possible Lung Cancer

    DEFF Research Database (Denmark)

    Mortensen; Enevoldsen; Friberg;

    2000-01-01

    clinical information, CT and PET findings. In principle, suspected metastatic lesions were biopsied before surgery. The gold standard was histology from biopsy or thoracotomy, or resolution of the X-ray findings and symptoms.Results: One patient was excluded because of uncertain diagnosis. In 3 (15......Purpose: To examine the value of PET in diagnosis and staging of suspected lung cancer.Methods: 20 (13 male; mean age: 56 yr., range: 22-83 yr.) patients with chest X-ray findings suspicious of malignancy were staged a) "clinically" (X-ray, history/physical examination, lung function), b) by chest......%) patients surgery was avoided mainly because of the PET findings. In one SCLC patient and one lymphoma patient, PET showed extensive disease, which changed the chemotherapy regime. Accuracy was 83% for clinical stage, 79% for CT and 77% for PET. Four (20%) false positive PET findings were caused...

  10. Laser-based X-ray and electron source for X-ray fluorescence studies

    Science.gov (United States)

    Valle Brozas, F.; Crego, A.; Roso, L.; Peralta Conde, A.

    2016-08-01

    In this work, we present a modification to conventional X-rays fluorescence using electrons as excitation source and compare it with the traditional X-ray excitation for the study of pigments. For this purpose, we have constructed a laser-based source capable to produce X-rays as well as electrons. Because of the large penetration depth of X-rays, the collected fluorescence signal is a combination of several material layers of the artwork under study. However, electrons are stopped in the first layers, allowing a more superficial analysis. We show that the combination of both excitation sources can provide extremely valuable information about the structure of the artwork.

  11. Extended X-ray Monitoring of Gravitational Lenses with Chandra and Joint Constraints on X-ray Emission Regions

    CERN Document Server

    Guerras, Eduardo; Steele, Shaun; Liu, Ang; Kochanek, Christopher S; Chartas, George; Morgan, Christopher W; Chen, Bin

    2016-01-01

    We present an X-ray photometric analysis of six gravitationally lensed quasars spanning from 5 to 14 years, measuring the total (0.83-21.8 keV restframe), soft (0.83-3.6 keV), and hard (3.6-21.8 keV) band image flux ratios for each epoch. Using the ratios of the model-predicted macro-magnifications as baselines, we build differential microlensing curves and obtain joint likelihood functions for the average X-ray emission region sizes. Our analysis yields a Probability Distribution Function for the average half-light radius of the X-Ray emission region in the sample that peaks slightly above 1 gravitational radius, and yields nearly indistinguishable 68 % confidence (one-sided) upper limits of 17.8 (18.9) gravitational radii for the soft (hard) X-ray emitting region, assuming a mean stellar mass of 0.3 solar masses. We see hints of energy dependent microlensing between the soft and hard bands in two of the objects. In a separate analysis on the root-mean-square (RMS) of the microlensing variability, we find si...

  12. Formation and X-ray Emission from Hot Bubbles in Planetary Nebulae. II. Hot bubble X-ray emission

    CERN Document Server

    Toalá, J A

    2016-01-01

    We present a study of the X-ray emission from numerical simulations of hot bubbles in planetary nebulae (PNe). High-resolution, two-dimensional, radiation-hydrodynamical simulations of the formation and evolution of hot bubbles in PNe, with and without thermal conduction, are used to calculate the X-ray emission and study its time-dependence and relationship to the changing stellar parameters. Instabilities in the wind-wind interaction zone produce clumps and filaments in the swept-up shell of nebular material. Turbulent mixing and thermal conduction at the corrugated interface can produce quantities of intermediate temperature and density gas between the hot, shocked wind bubble and the swept-up photoionized nebular material, which can emit in soft, diffuse X-rays. We use the CHIANTI software to compute synthetic spectra for the models and calculate their luminosities. We find that models both with conduction and those without can produce the X-ray temperatures and luminosities that are in the ranges reporte...

  13. On the dependence of the X-ray continuum variations with luminosity in accreting X-ray pulsars

    CERN Document Server

    Postnov, K A; Klochkov, D; Laplace, E; Lukin, V V; Shakura, N I

    2015-01-01

    Using RXTE/ASM archival data, we investigate the behaviour of the spectral hardness ratio as a function of X-ray luminosity in a sample of six transient X-ray pulsars (EXO 2030+375, GX 304-1, 4U 0115+63, V 0332+63, A 0535+26 and MXB 0656-072). In all sources we find that the spectral hardness ratio defined as $F_{5-12\\mathrm{keV}}/ F_{1.33-3\\mathrm{keV}}$ increases with the ASM flux (1.33--12 keV) at low luminosities and then saturates or even slightly decreases above some critical X-ray luminosity falling into the range $\\sim(3-7)\\times10^{37}$~erg~s$^{-1}$. Two-dimensional structure of accretion columns in the radiation-diffusion limit is calculated for two possible geometries (filled and hollow cylinder) for mass accretion rates $\\dot M$ ranging from $10^{17}$ to 1.2$\\times 10^{18}$~g s$^{-1}$. The observed spectral behaviour in the transient X-ray pulsars with increasing $\\dot M$ can be reproduced by a Compton saturated sidewall emission from optically thick magnetized accretion columns with taking into a...

  14. The Host Galaxies of X-ray Quasars Are Not Strong Star Formers

    CERN Document Server

    Barger, A J; Owen, F N; Chen, C -C; Hasinger, G; Hsu, L -Y; Li, Y

    2014-01-01

    We use ultradeep SCUBA-2 850um observations (~0.37 mJy rms) of the 2 Ms CDF-N and 4 Ms CDF-S X-ray fields to examine the amount of dusty star formation taking place in the host galaxies of high-redshift X-ray AGNs. Supplementing with COSMOS, we measure the submillimeter fluxes of the 4-8 keV sources at z>1, finding little flux at the highest X-ray luminosities but significant flux at intermediate luminosities. We determine grey body and MIR luminosities by fitting spectral energy distributions to each X-ray source and to each radio source in an ultradeep Karl G. Jansky VLA 1.4 GHz (11.5uJy at 5-sigma) image of the CDF-N. We confirm the FIR-radio and MIR-radio correlations to z=4 using the non-X-ray detected radio sources. Both correlations are also obeyed by the X-ray less luminous AGNs but not by the X-ray quasars. We interpret the low FIR luminosities relative to the MIR for the X-ray quasars as being due to a lack of star formation, while the MIR stays high due to the AGN contribution. We find that the FIR...

  15. Structure determination by X-ray crystallography

    CERN Document Server

    Ladd, M F C

    1977-01-01

    Crystallography may be described as the science of the structure of materi­ als, using this word in its widest sense, and its ramifications are apparent over a broad front of current scientific endeavor. It is not surprising, therefore, to find that most universities offer some aspects of crystallography in their undergraduate courses in the physical sciences. It is the principal aim of this book to present an introduction to structure determination by X-ray crystal­ lography that is appropriate mainly to both final-year undergraduate studies in crystallography, chemistry, and chemical physics, and introductory post­ graduate work in this area of crystallography. We believe that the book will be of interest in other disciplines, such as physics, metallurgy, biochemistry, and geology, where crystallography has an important part to play. In the space of one book, it is not possible either to cover all aspects of crystallography or to treat all the subject matter completely rigorously. In particular, certain ...

  16. X-ray spectral states of microquasars

    CERN Document Server

    Malzac, Julien

    2008-01-01

    We discuss the origin of the dramatically different X-ray spectral shapes observed in the Low Hard State (LHS: dominated by thermal comptonisation) and the High Soft State (HSS: dominated by the accretion disc thermal emission and non-thermal comptonisation in the corona). We present numerical simulations using a new code accounting for the so-called synchrotron boiler effect. These numerical simulations when compared to the data allow us to constrain the magnetic field and temperature of the hot protons in the corona. For the hard state of Cygnus X-1 we find a magnetic field below equipartition with radiation, suggesting that the corona is not powered through magnetic field dissipation (as assumed in most accretion disc corona models). On the other hand, our results also point toward proton temperatures that are substantially lower than typical temperatures of the ADAF models. Finally, we show that in both spectral states Comptonising plasma could be powered essentially through power-law acceleration of non-...

  17. Low energy x-ray spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Woodruff, W.R.

    1981-06-05

    A subkilovolt spectrometer has been produced to permit high-energy-resolution, time-dependent x-ray intensity measurements. The diffracting element is a curved mica (d = 9.95A) crystal. To preclude higher order (n > 1) diffractions, a carbon x-ray mirror that reflects only photons with energies less than approx. 1.1 keV is utilized ahead of the diffracting element. The nominal energy range of interest is 800 to 900 eV. The diffracted photons are detected by a gold-surface photoelectric diode designed to have a very good frequency response, and whose current is recorded on an oscilloscope. A thin, aluminium light barrier is placed between the diffracting crystal and the photoelectric diode detector to keep any uv generated on or scattered by the crystal from illuminating the detector. High spectral energy resolution is provided by many photocathodes between 8- and 50-eV wide placed serially along the diffracted x-ray beam at the detector position. The spectrometer was calibrated for energy and energy dispersion using the Ni L..cap alpha../sub 1/ /sub 2/ lines produced in the LLNL IONAC accelerator and in third order using a molybdenum target x-ray tube. For the latter calibration the carbon mirror was replaced by one surfaced with rhodium to raise the cut-off energy to about 3 keV. The carbon mirror reflection dependence on energy was measured using one of our Henke x-ray sources. The curved mica crystal diffraction efficiency was measured on our Low-Energy x-ray (LEX) machine. The spectrometer performs well although some changes in the way the x-ray mirror is held are desirable. 16 figures.

  18. Handbook of X-Ray Astronomy

    Science.gov (United States)

    Arnaud, Keith A. (Editor); Smith, Randall K.; Siemiginowska, Aneta

    2011-01-01

    X-ray astronomy was born in the aftermath of World War II as military rockets were repurposed to lift radiation detectors above the atmosphere for a few minutes at a time. These early flights detected and studied X-ray emission from the Solar corona. The first sources beyond the Solar System were detected during a rocket flight in 1962 by a team headed by Riccardo Giaccom at American Science and Engineering, a company founded by physicists from MIT. The rocket used Geiger counters with a system designed to reduce non-X-ray backgrounds and collimators limiting the region of sky seen by the counters. As the rocket spun, the field of view (FOV) happened to pass over what was later found to be the brightest non-Solar X-ray source; later designated See X-1. It also detected a uniform background glow which could not be resolved into individual sources. A follow-up campaign using X-ray detectors with better spatial resolution and optical telescopes identified See X-1 as an interacting binary with a compact (neutron star) primary. This success led to further suborbital rocket flights by a number of groups. More X-ray binaries were discovered, as well as X-ray emission from supernova remnants, the radio galaxies M87 and Cygnus-A, and the Coma cluster. Detectors were improved and Geiger counters were replaced by proportional counters, which provided information about energy spectra of the sources. A constant challenge was determining precise positions of sources as only collimators were available.

  19. Normal incidence X-ray telescope power spectra of X-ray emission from solar active regions. I - Observations. II - Theory

    Science.gov (United States)

    Gomez, Daniel O.; Martens, Petrus C. H.; Golub, Leon

    1993-01-01

    Fourier analysis is applied to very high resolution image of coronal active regions obtained by the Normal Incidence X-Ray Telescope is used to find a broad isotropic power-law spectrum of the spatial distribution of soft X-ray intensities. Magnetic structures of all sizes are present down to the resolution limit of the instrument. Power spectra for the X-ray intensities of a sample of topologically different active regions are found which fall off with increasing wavenumber as 1/k-cubed. A model is presented that relates the basic features of coronal magnetic fluctuations to the subphotospheric hydrodynamic turbulence that generates them. The model is used to find a theoretical power spectrum for the X-ray intensity which falls off with increasing wavenumber as 1/k-cubed. The implications of a turbulent regime in active regions are discussed.

  20. New achievements in X-ray optics——the X-ray lens and its applications

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An X-ray lens consists of a large number of X-ray capillaries. It can collect divergent X-rays emitted from an X-ray source and form a focused or parallel beam of high intensity. So it is an effective tool for adjusting and controlling wide bandwidth X-ray beams. In this paper, the X-ray lens made by the X-ray Optics Laboratory of Institute of Low Energy Nuclear Physics at Beijing Normal University and its applications in the field of X-ray analysis are presented.

  1. THE CHANDRA LOCAL VOLUME SURVEY: THE X-RAY POINT-SOURCE POPULATION OF NGC 404

    Energy Technology Data Exchange (ETDEWEB)

    Binder, B.; Williams, B. F.; Weisz, D. R. [University of Washington, Department of Astronomy, Box 351580, Seattle, WA 98195 (United States); Eracleous, M. [Department of Astronomy and Astrophysics and Center for Gravitational Wave Physics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Gaetz, T. J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street Cambridge, MA 02138 (United States); Kong, A. K. H. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Skillman, E. D. [University of Minnesota, Astronomy Department, 116 Church St. SE, Minneapolis, MN 55455 (United States)

    2013-02-15

    We present a comprehensive X-ray point-source catalog of NGC 404 obtained as part of the Chandra Local Volume Survey. A new 97 ks Chandra ACIS-S observation of NGC 404 was combined with archival observations for a total exposure of {approx}123 ks. Our survey yields 74 highly significant X-ray point sources and is sensitive to a limiting unabsorbed luminosity of {approx}6 Multiplication-Sign 10{sup 35} erg s{sup -1} in the 0.35-8 keV band. To constrain the nature of each X-ray source, cross-correlations with multi-wavelength data were generated. We searched overlapping Hubble Space Telescope observations for optical counterparts to our X-ray detections, but find only two X-ray sources with candidate optical counterparts. We find 21 likely low-mass X-ray binaries (LMXBs), although this number is a lower limit due to the difficulties in separating LMXBs from background active galactic nuclei. The X-ray luminosity functions (XLFs) in both the soft and hard energy bands are presented. The XLFs in the soft band (0.5-2 keV) and the hard band (2-8 keV) have a limiting luminosity at the 90% completeness limit of 10{sup 35} erg s{sup -1} and 10{sup 36} erg s{sup -1}, respectively, significantly lower than previous X-ray studies of NGC 404. We find the XLFs to be consistent with those of other X-ray populations dominated by LMXBs. However, the number of luminous (>10{sup 37} erg s{sup -1}) X-ray sources per unit stellar mass in NGC 404 is lower than is observed for other galaxies. The relative lack of luminous XRBs may be due to a population of LMXBs with main-sequence companions formed during an epoch of elevated star formation {approx}0.5 Gyr ago.

  2. X-Ray Calorimeter Arrays for Astrophysics

    Science.gov (United States)

    Kilbourne, Caroline A.

    2009-01-01

    High-resolution x-ray spectroscopy is a powerful tool for studying the evolving universe. The grating spectrometers on the XMM and Chandra satellites started a new era in x-ray astronomy, but there remains a need for instrumentation that can provide higher spectral resolution with high throughput in the Fe-K band (around 6 keV) and can enable imaging spectroscopy of extended sources, such as supernova remnants and galaxy clusters. The instrumentation needed is a broad-band imaging spectrometer - basically an x-ray camera that can distinguish tens of thousands of x-ray colors. The potential benefits to astrophysics of using a low-temperature calorimeter to determine the energy of an incident x-ray photon via measurement of a small change in temperature was first articulated by S. H. Moseley over two decades ago. In the time since, technological progress has been steady, though full realization in an orbiting x-ray telescope is still awaited. A low-temperature calorimeter can be characterized by the type of thermometer it uses, and three types presently dominate the field. The first two types are temperature-sensitive resistors - semiconductors in the metal-insulator transition and superconductors operated in the superconducting-normal transition. The third type uses a paramagnetic thermometer. These types can be considered the three generations of x-ray calorimeters; by now each has demonstrated a resolving power of 2000 at 6 keV, but only a semiconductor calorimeter system has been developed to spaceflight readiness. The Soft X-ray Spectrometer on Astro-H, expected to launch in 2013, will use an array of silicon thermistors with I-IgTe x-ray absorbers that will operate at 50 mK. Both the semiconductor and superconductor calorimeters have been implemented in small arrays, kilo-pixel arrays of the superconducting calorimeters are just now being produced, and it is anticipated that much larger arrays will require the non-dissipative advantage of magnetic thermometers.

  3. Optics for coherent X-ray applications.

    Science.gov (United States)

    Yabashi, Makina; Tono, Kensuke; Mimura, Hidekazu; Matsuyama, Satoshi; Yamauchi, Kazuto; Tanaka, Takashi; Tanaka, Hitoshi; Tamasaku, Kenji; Ohashi, Haruhiko; Goto, Shunji; Ishikawa, Tetsuya

    2014-09-01

    Developments of X-ray optics for full utilization of diffraction-limited storage rings (DLSRs) are presented. The expected performance of DLSRs is introduced using the design parameters of SPring-8 II. To develop optical elements applicable to manipulation of coherent X-rays, advanced technologies on precise processing and metrology were invented. With propagation-based coherent X-rays at the 1 km beamline of SPring-8, a beryllium window fabricated with the physical-vapour-deposition method was found to have ideal speckle-free properties. The elastic emission machining method was utilized for developing reflective mirrors without distortion of the wavefronts. The method was further applied to production of diffraction-limited focusing mirrors generating the smallest spot size in the sub-10 nm regime. To enable production of ultra-intense nanobeams at DLSRs, a low-vibration cooling system for a high-heat-load monochromator and advanced diagnostic systems to characterize X-ray beam properties precisely were developed. Finally, new experimental schemes for combinative nano-analysis and spectroscopy realised with novel X-ray optics are discussed.

  4. Nonlinear X-ray Compton Scattering

    CERN Document Server

    Fuchs, Matthias; Chen, Jian; Ghimire, Shambhu; Shwartz, Sharon; Kozina, Michael; Jiang, Mason; Henighan, Thomas; Bray, Crystal; Ndabashimiye, Georges; Bucksbaum, P H; Feng, Yiping; Herrmann, Sven; Carini, Gabriella; Pines, Jack; Hart, Philip; Kenney, Christopher; Guillet, Serge; Boutet, Sebastien; Williams, Garth; Messerschmidt, Marc; Seibert, Marvin; Moeller, Stefan; Hastings, Jerome B; Reis, David A

    2015-01-01

    X-ray scattering is a weak linear probe of matter. It is primarily sensitive to the position of electrons and their momentum distribution. Elastic X-ray scattering forms the basis of atomic structural determination while inelastic Compton scattering is often used as a spectroscopic probe of both single-particle excitations and collective modes. X-ray free-electron lasers (XFELs) are unique tools for studying matter on its natural time and length scales due to their bright and coherent ultrashort pulses. However, in the focus of an XFEL the assumption of a weak linear probe breaks down, and nonlinear light-matter interactions can become ubiquitous. The field can be sufficiently high that even non-resonant multiphoton interactions at hard X-rays wavelengths become relevant. Here we report the observation of one of the most fundamental nonlinear X-ray-matter interactions, the simultaneous Compton scattering of two identical photons producing a single photon at nearly twice the photon energy. We measure scattered...

  5. Imaging in Hard X-ray Astronomy

    CERN Document Server

    Li Ti Pei

    2002-01-01

    The energy range of hard X-rays is a key waveband to the study of high energy processes in celestial objects, but still remains poorly explored. In contrast to direct imaging methods used in the low energy X-ray and high energy gamma-ray bands, currently imaging in the hard X-ray band is mainly achieved through various modulation techniques. A new inversion technique, the direct demodulation method, has been developed since early 90s. With this technique, wide field and high resolution images can be derived from scanning data of a simple collimated detector. The feasibility of this technique has been confirmed by experiment, balloon-borne observation and analyzing simulated and real astronomical data. Based the development of methodology and instrumentation, a high energy astrophysics mission -- Hard X-ray Modulation Telescope (HXMT) has been proposed and selected in China for a four-year Phase-A study. The main scientific objectives are a full-sky hard X-ray (20-200 keV) imaging survey and high signal-to-noi...

  6. X-ray emission processes in stars

    CERN Document Server

    Testa, Paola

    2010-01-01

    A decade of X-ray stellar observations with Chandra and XMM-Newton has led to significant advances in our understanding of the physical processes at work in hot (magnetized) plasmas in stars and their immediate environment, providing new perspectives and challenges, and in turn the need for improved models. The wealth of high-quality stellar spectra has allowed us to investigate, in detail, the characteristics of the X-ray emission across the HR diagram. Progress has been made in addressing issues ranging from classical stellar activity in stars with solar-like dynamos (such as flares, activity cycles, spatial and thermal structuring of the X-ray emitting plasma, evolution of X-ray activity with age), to X-ray generating processes (e.g. accretion, jets, magnetically confined winds) that were poorly understood in the pre-Chandra/XMM-Newton era. I discuss the progress made in the study of high energy stellar physics and its impact in a wider astrophysical context, focusing on the role of spectral diagnostics no...

  7. X-ray echo spectroscopy (Conference Presentation)

    Science.gov (United States)

    Shvyd'ko, Yuri V.

    2016-09-01

    X-ray echo spectroscopy, a counterpart of neutron spin-echo, was recently introduced [1] to overcome limitations in spectral resolution and weak signals of the traditional inelastic x-ray scattering (IXS) probes. An image of a point-like x-ray source is defocused by a dispersing system comprised of asymmetrically cut specially arranged Bragg diffracting crystals. The defocused image is refocused into a point (echo) in a time-reversal dispersing system. If the defocused beam is inelastically scattered from a sample, the echo signal acquires a spatial distribution, which is a map of the inelastic scattering spectrum. The spectral resolution of the echo spectroscopy does not rely on the monochromaticity of the x-rays, ensuring strong signals along with a very high spectral resolution. Particular schemes of x-ray echo spectrometers for 0.1-meV and 0.02-meV ultra-high-resolution IXS applications (resolving power > 10^8) with broadband 5-13 meV dispersing systems will be presented featuring more than 1000-fold signal enhancement. The technique is general, applicable in different photon frequency domains. [1.] Yu. Shvyd'ko, Phys. Rev. Lett. 116, accepted (2016), arXiv:1511.01526.

  8. X-ray absorption spectroscopy of metalloproteins.

    Science.gov (United States)

    Ward, Jesse; Ollmann, Emily; Maxey, Evan; Finney, Lydia A

    2014-01-01

    Metalloproteins are enormously important in biology. While a variety of techniques exist for studying metals in biology, X-ray absorption spectroscopy is particularly useful in that it can determine the local electronic and physical structure around the metal center, and is one of the few avenues for studying "spectroscopically silent" metal ions like Zn(II) and Cu(I) that have completely filled valence bands. While X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) are useful for studying metalloprotein structure, they suffer the limitation that the detected signal is an average of all the various metal centers in the sample, which limits its usefulness for studying metal centers in situ or in cell lysates. It would be desirable to be able to separate the various proteins in a mixture prior to performing X-ray absorption studies, so that the derived signal is from one species only. Here we describe a method for performing X-ray absorption spectroscopy on protein bands following electrophoretic separation and western blotting.

  9. X-ray spectroscopy an introduction

    CERN Document Server

    Agarwal, Bipin K

    1979-01-01

    Rontgen's discovery of X-rays in 1895 launched a subject which became central to the development of modern physics. The verification of many of the predic­ tions of quantum theory by X-ray spectroscopy in the early part of the twen­ tieth century stimulated great interest in thi's area, which has subsequently influenced fields as diverse as chemical physics, nuclear physics, and the study of the electronic properties of solids, and led to the development of techniques such as Auger, Raman, and X-ray photoelectron spectroscopy. The improvement of the theoretical understanding of the physics underlying X-ray spectroscopy has been accompanied by advances in experimental techniques, and the subject provides an instructive example of how progress on both these fronts can be mutually beneficial. This book strikes a balance between his­ torical description, which illustrates this symbiosis, and the discussion of new developments. The application of X-ray spectroscopic methods to the in­ vestigation of chemical b...

  10. Ultrafast X-Ray Coherent Control

    Energy Technology Data Exchange (ETDEWEB)

    Reis, David

    2009-05-01

    This main purpose of this grant was to develop the nascent eld of ultrafast x-ray science using accelerator-based sources, and originally developed from an idea that a laser could modulate the di racting properties of a x-ray di racting crystal on a fast enough time scale to switch out in time a shorter slice from the already short x-ray pulses from a synchrotron. The research was carried out primarily at the Advanced Photon Source (APS) sector 7 at Argonne National Laboratory and the Sub-Picosecond Pulse Source (SPPS) at SLAC; in anticipation of the Linac Coherent Light Source (LCLS) x-ray free electron laser that became operational in 2009 at SLAC (all National User Facilities operated by BES). The research centered on the generation, control and measurement of atomic-scale dynamics in atomic, molecular optical and condensed matter systems with temporal and spatial resolution . It helped develop the ultrafast physics, techniques and scienti c case for using the unprecedented characteristics of the LCLS. The project has been very successful with results have been disseminated widely and in top journals, have been well cited in the eld, and have laid the foundation for many experiments being performed on the LCLS, the world's rst hard x-ray free electron laser.

  11. Supergiant Fast X-ray Transients

    CERN Document Server

    Sidoli, Lara

    2011-01-01

    The phenomenology of a subclass of High Mass X-ray Binaries hosting a blue supergiant companion, the so-called Supergiant Fast X-ray Transients (SFXTs), is reviewed. Their number is growing, mainly thanks to the discoveries performed by the INTEGRAL satellite, then followed by soft X-rays observations (both aimed at refining the source position and at monitoring the source behavior) leading to the optical identification of the blue supergiant nature of the donor star. Their defining properties are a transient X-ray activity consisting of sporadic, fast and bright flares, (each with a variable duration between a few minutes and a few hours), reaching 1E36-1E37 erg/s. The quiescence is at a luminosity of 1E32 erg/s, while their more frequent state consists of an intermediate X-ray emission of 1E33-1E34 erg/s (1-10 keV). Only the brightest flares are detected by INTEGRAL (>17 keV) during short pointings, with no detected persistent emission. The physical mechanism driving the short outbursts is still debated, al...

  12. Results of a dosimetry study in the European Community on frequent X ray examinations in infants

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, K.; Fendel, H.; Bakowski, C. (Muenchen Univ. (Germany). Kinderklinik) (and others)

    1992-01-01

    This Europe-wide dosimetry study, covering 89 departments in 11 EC countries, measured entrance surface dose (ESD) using TLDs, and surveyed X ray equipment and radiographic techniques used for frequent paediatric X ray examinations of the chest, abdomen, pelvis, skull and spine. The survey was limited to infants (10 months, 4 months and prematures of [approx] 1 kg). Data analysis showed widely differing radiographic techniques. This was one of the reasons for the large variations in ESD of an order of magnitude of 1:50. A substantial number of departments used either very old X ray generators and/or techniques poorly suited for paediatric radiology. Significant dose reduction was seen when recommended guidelines for good radiographic technique were followed. This study emphasises the necessity for the adherence to easily followed guidelines for the improvement of training and equipment in paediatric radiology. (author).

  13. Advancing x-ray scattering metrology using inverse genetic algorithms

    Science.gov (United States)

    Hannon, Adam F.; Sunday, Daniel F.; Windover, Donald; Joseph Kline, R.

    2016-07-01

    We compare the speed and effectiveness of two genetic optimization algorithms to the results of statistical sampling via a Markov chain Monte Carlo algorithm to find which is the most robust method for determining real-space structure in periodic gratings measured using critical dimension small-angle x-ray scattering. Both a covariance matrix adaptation evolutionary strategy and differential evolution algorithm are implemented and compared using various objective functions. The algorithms and objective functions are used to minimize differences between diffraction simulations and measured diffraction data. These simulations are parameterized with an electron density model known to roughly correspond to the real-space structure of our nanogratings. The study shows that for x-ray scattering data, the covariance matrix adaptation coupled with a mean-absolute error log objective function is the most efficient combination of algorithm and goodness of fit criterion for finding structures with little foreknowledge about the underlying fine scale structure features of the nanograting.

  14. On Neutral Absorption and Spectral Evolution in X-ray Binaries

    CERN Document Server

    Miller, J M; Reis, R C

    2009-01-01

    Current X-ray observatories make it possible to follow the evolution of transient and variable X-ray binaries across a broad range in luminosity and source behavior. In such studies, it can be unclear whether evolution in the low energy portion of the spectrum should be attributed to evolution in the source, or instead to evolution in neutral photoelectric absorption. Dispersive spectrometers make it possible to address this problem. We have analyzed a small but diverse set of X-ray binaries observed with the Chandra High Energy Transmission Grating Spectrometer across a range in luminosity and different spectral states. The column density in individual photoelectric absorption edges remains constant with luminosity, both within and across source spectral states. This finding suggests that absorption in the interstellar medium strongly dominates the neutral column density observed in spectra of X-ray binaries. Consequently, evolution in the low energy spectrum of X-ray binaries should properly be attributed t...

  15. On the X-ray variability of magnetar 1RXS J170849.0–400910

    Energy Technology Data Exchange (ETDEWEB)

    Scholz, P.; Archibald, R. F.; Kaspi, V. M.; Ng, C.-Y. [Department of Physics, Rutherford Physics Building, McGill University, 3600 University Street, Montreal, Quebec, H3A 2T8 (Canada); Beardmore, A. P. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Gehrels, N. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Kennea, J. A., E-mail: pscholz@phsyics.mcgill.ca [Department of Astronomy and Astrophysics, 525 Davey Lab, Pennsylvania State University, University Park, PA 16802 (United States)

    2014-03-10

    We present a long-term X-ray flux and spectral analysis for 1RXS J170849.0–400910 using the Swift/X-Ray Telescope spanning over eight years from 2005 to 2013. We also analyze two observations from Chandra and XMM in the period from 2003 to 2004. In this ten-year period, 1RXS J170849.0–400910 displayed several rotational glitches. Previous studies have claimed variations in the X-ray emission associated with some of the glitches. From our analysis we find no evidence for significant X-ray flux variations and evidence for only low-level spectral variations. We also present an updated timing solution for 1RXS J170849.0–400910, from Rossi X-ray Timing Explorer and Swift observations, which includes a previously unreported glitch at MJD 56019. We discuss the frequency and implications of radiatively quiet glitches in magnetars.

  16. Suzaku Detection of Diffuse Hard X-Ray Emission outside Vela X

    CERN Document Server

    Katsuda, Satoru; Petre, Robert; Yamaguchi, Hiroya; Tsunemi, Hiroshi; Bocchino, Fabrizio; Bamba, Aya; Miceli, Marco; Hewitt, John W; Temim, Tea; Uchida, Hiroyuki; Yoshii, Rie

    2011-01-01

    Vela X is a large, 3x2 degrees, radio-emitting pulsar wind nebula (PWN) powered by the Vela pulsar in the Vela supernova remnant. Using four Suzaku/XIS observations pointed just outside Vela X, we find hard X-ray emission extending throughout the fields of view. The hard X-ray spectra are well represented by a power-law. The photon index is measured to be constant at Gamma~2.4, similar to that of the southern outer part of Vela X. The power-law flux decreases with increasing distance from the pulsar. These properties lead us to propose that the hard X-ray emission is associated with the Vela PWN. The larger X-ray extension found in this work strongly suggests that distinct populations relativistic electrons form the X-ray PWN and Vela X, as was recently inferred from multiwavelength spectral modeling of Vela X.

  17. Suzaku Detection of Diffuse Hard X-Ray Emission Outside Vela X

    Science.gov (United States)

    Katsuda, Satoru; Mori, Koji; Petre, Robert; Yamaguchi, Hiroya; Tsunemi, Hiroshi; Bocchino, Fabrizio; Bamba, Aya; Miceli, Marco; Hewitt, John W.; Temim, Tea; Uchida, Hiroyuki; Yoshii, Rie

    2011-01-01

    Vela X is a large, 3 deg x 2 deg, radio-emitting pulsar wind nebula (PWN) powered by the Vela pulsar in the Vela supernova remnant. Using four Suzaku/XIS observations pointed just outside Vela X, we find hard X-ray emission extending throughout the fields of view. The hard X-ray spectra are well represented by a power-law. The photon index is measured to be constant at Gamma approximates 2.4, similar to that of the southern outer part of Vela X. The power-law flux decreases with increasing distance from the pulsar. These properties lead us to propose that the hard X-ray emission is associated with the Vela PWN. The larger X-ray extension found in this work strongly suggests that distinct populations relativistic electrons form the X-ray PWN and Vela X, as was recently inferred from multiwavelength spectral modeling of Vela X.

  18. VizieR Online Data Catalog: Intermediate-luminosity X-ray objects catalog (Colbert+, 2002)

    Science.gov (United States)

    Colbert, E. J. M.; Ptak, A. F.

    2002-11-01

    ROSAT, and now Chandra, X-ray images allow studies of extranuclear X-ray point sources in galaxies other than our own. X-ray observations of normal galaxies with ROSAT and Chandra have revealed that off-nuclear, compact, intermediate-luminosity (LX[2-10keV]>=1039erg/s) X-ray objects (IXOs, a.k.a. ULXs [ultraluminous X-ray sources]) are quite common. Here we present a catalog and finding charts for 87 IXOs in 54 galaxies, derived from all of the ROSAT HRI imaging data for galaxies with cz<=5000km/s from the Third Reference Catalog of Bright Galaxies. (2 data files).

  19. Suppression of X-rays during an optical outburst of the helium dwarf nova KL Dra

    CERN Document Server

    Ramsay, Gavin; Rosen, Simon; Barclay, Thomas; Steeghs, Danny

    2012-01-01

    KL Dra is a helium accreting AM CVn binary system with an orbital period close to 25 mins. Approximately every 60 days there is a 4 mag optical outburst lasting ~10 days. We present the most sensitive X-ray observations made of an AM CVn system during an outburst cycle. A series of eight observations were made using XMM-Newton which started shortly after the onset of an optical outburst. We find that X-rays are suppressed during the optical outburst. There is some evidence for a spectral evolution of the X-ray spectrum during the course of the outburst. A periodic modulation is seen in the UV data at three epochs -- this is a signature of the binary orbital or the super-hump period. The temperature of the X-ray emitting plasma is cooler compared to dwarf novae, which may suggest a wind is the origin of a significant fraction of the X-ray flux.

  20. Evidence of Bulk Acceleration of the GRB X-Ray Flare Emission Region

    Science.gov (United States)

    Uhm, Z. Lucas; Zhang, Bing

    2016-06-01

    Applying our recently developed generalized version of the high-latitude emission theory to the observations of X-ray flares in gamma-ray bursts (GRBs), here we present clear observational evidence that the X-ray flare emission region is undergoing rapid bulk acceleration as the photons are emitted. We show that both the observed X-ray flare light curves and the photon index evolution curves can be simultaneously reproduced within a simple physical model invoking synchrotron radiation in an accelerating emission region far from the GRB central engine. Such an acceleration process demands an additional energy dissipation source other than kinetic energy, which points toward a significant Poynting flux in the emission region of X-ray flares. As the X-ray flares are believed to share a similar physical mechanism as the GRB prompt emission, our finding here hints that the GRB prompt emission jets may also carry a significant Poynting flux in their emitting region.

  1. A statistical study of the relation between soft X-ray excess and accretion disk

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    To study the origin of the soft X-ray excess,we compile a sample of 94 unobscured,radio-quiet QSOs and Seyfert galaxies with available data from GALEX and ROSAT.We find that 50 sources show strong soft X-ray excess and the other 44 show weak/no soft X-ray excess.Systematic analyses of the data indicate that the difference in soft X-rays is mainly but not only resulting from different accretion rates(in units of Eddington rate).The statistical study of the sources with soft X-ray excess shows that the strength of soft X-ray excess weakly and positively correlates with the Eddington ratio and increases with the increase of the strength of UV radiations relative to the X-rays.Provided that the UV emissions are from the thin disk,the correlations imply that the origin of soft X-ray excess is associated with the thin disk,either by means of Comptonization of the disk photons or in some other ways.

  2. Multiwavelength Study of Chandra X-Ray Sources in the Antennae

    CERN Document Server

    Clark, D M; Brandl, B R; Wilson, J C; Carson, J C; Henderson, C P; Hayward, T L; Barry, D J; Ptak, A F; Colbert, E J M

    2010-01-01

    We use WIRC, IR images of the Antennae (NGC 4038/4039) together with the extensive catalogue of 120 X-ray point sources (Zezas et al. 2006) to search for counterpart candidates. Using our proven frame-tie technique, we find 38 X-ray sources with IR counterparts, almost doubling the number of IR counterparts to X-ray sources first identified in Clark et al. (2007). In our photometric analysis, we consider the 35 IR counterparts that are confirmed star clusters. We show that the clusters with X-ray sources tend to be brighter, K_s ~16 mag, with (J-K_s) = 1.1 mag. We then use archival HST images of the Antennae to search for optical counterparts to the X-ray point sources. We employ our previous IR-to-X-ray frame-tie as an intermediary to establish a precise optical-to-X-ray frame-tie with <0.6 arcsec rms positional uncertainty. Due to the high optical source density near the X-ray sources, we determine that we cannot reliably identify counterparts. Comparing the HST positions to the 35 identified IR star clu...

  3. An X-ray Imaging Survey of Quasar Jets -- Testing the Inverse Compton Model

    CERN Document Server

    Marshall, H L; Schwartz, D A; Murphy, D W; Lovell, J E J; Worrall, D M; Birkinshaw, M; Perlman, E S; Godfrey, L; Jauncey, D L

    2011-01-01

    We present results from continued Chandra X-ray imaging and spectroscopy of a flux-limited sample of flat spectrum radio-emitting quasars with jet-like extended structure. X-rays are detected from 24 of the 39 jets observed so far. We compute the distribution of alpha_rx, the spectral index between the X-ray and radio bands, showing that it is broad, extending at least from 0.8 to 1.2. While there is a general trend that the radio brightest jets are detected most often, it is clear that predicting the X-ray flux from the radio knot flux densities is risky so a shallow X-ray survey is the most effective means for finding jets that are X-ray bright. We test the model in which the X-rays result from inverse Compton (IC) scattering of cosmic microwave background (CMB) photons by relativistic electrons in the jet moving with high bulk Lorentz factor nearly along the line of sight. Depending on how the jet magnetic fields vary with z, the observed X-ray to radio flux ratios do not follow the redshift dependence exp...

  4. X-ray AGN in the XMM-LSS galaxy clusters: no evidence for AGN suppression

    CERN Document Server

    Koulouridis, E; Melnyk, O; Elyiv, A; Georgantopoulos, I; Clerc, N; Surdej, J; Chiappetti, L; Pierre, M

    2014-01-01

    We present a study of the overdensity of X-ray selected AGN in 33 galaxy clusters in the XMM-LSS field, up to redhift z=1.05. Previous studies have shown that the presence of X-ray selected AGN in rich galaxy clusters is suppressed. In the current study we investigate the occurrence of X-ray selected AGN in low and moderate X-ray luminosity galaxy clusters. Due to the wide contiguous XMM-LSS survey area we are able to extend the study to the cluster outskirts. We therefore determine the projected overdensity of X-ray point-like sources out to 6r_{500} radius. To provide robust statistical results we also use a stacking analysis of the cluster projected overdensities. We investigate whether the observed X-ray overdensities are to be expected by estimating also the corresponding optical galaxy overdensities. We find a positive X-ray projected overdensity at the first radial bin, which is however of the same amplitude as that of optical galaxies. Therefore, no suppression of X-ray AGN activity with respect to th...

  5. Comparison of chest-CT findings of Influenza virus-associated pneumonia in immunocompetent vs. immunocompromised patients

    Energy Technology Data Exchange (ETDEWEB)

    Kloth, C., E-mail: christopher.kloth@med.uni-tuebingen.de [Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tübingen (Germany); Forler, S.; Gatidis, S. [Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tübingen (Germany); Beck, R. [Institute of Medical Virology and Epidemiology of Viral Diseases, Eberhard-Karls-University, Elfriede-Aulhorn-Straße 6, 72076 Tübingen (Germany); Spira, D.; Nikolaou, K.; Horger, M. [Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str. 3, 72076 Tübingen (Germany)

    2015-06-15

    Highlights: • Patterns of pulmonary infiltration caused by Influenza viruses do not significantly differ between immunocompetent and immunocompromised patients or between different types and subtypes of Influenza virus. • Patterns of pulmonary infiltration caused by Influenza viruses seem to be interchangeable which might in part explain the great overlap in CT-imaging findings that has been reported in the past. • Interestingly, pattern transition from interstitial into airway-centric pattern seems to be frequent in immunocompromised patients receiving specific antiviral therapy, whereas the conversion of the airway-centric pattern into an interstitial pattern was observed more frequent in immunocompetent patients developing ARDS. - Abstract: Purpose: To retrospectively compare CT-patterns of pulmonary infiltration caused by different Influenza virus types and subtypes in immunocompetent and immunocompromised patients for possible discrimination. Materials and methods: Retrospective database search at our institution yielded 237 patients who were tested positive for Influenza virus type A or type B by bronchoalveolar lavage between January 2009 and April 2014. Fifty-six of these patients (female 26; male 30; median age 55.8 y, range 17–86 y; SD ± 14.4 y) underwent chest-HRCT due to a more severe clinical course of pulmonary infection. We registered all CT-findings compatible with pulmonary infection classifying them as airway predominant (tree-in-bud, centrilobular nodules, bronchial wall thickening ± peribronchial ground-glass opacity and consolidation) vs. interstitial-parenchymal predominant (bilateral, symmetrical GGO, consolidation, crazy paving and/or interlobular septal thickening). Twenty-six patients (46.4%) had follow-up CT-studies (0.78 mean, SD ± 5.8 scans). Results: Thirty-six patients were immunocompromised (group I) whereas 20 patients were immunocompetent (group II). An airway-centric pattern of infection was found in 15 patients (group

  6. Femtosecond X-ray Absorption Spectroscopy at a Hard X-ray Free Electron Laser

    DEFF Research Database (Denmark)

    Lemke, Henrik T.; Bressler, Christian; Chen, Lin X.

    2013-01-01

    X-ray free electron lasers (XFELs) deliver short (<100 fs) and intense (similar to 10(12) photons) pulses of hard X-rays, making them excellent sources for time-resolved studies. Here we show that, despite the inherent instabilities of current (SASE based) XFELs, they can be used for measuring hi...

  7. X-ray Spectral Variation of Eta Carinae through the 2003 X-ray Minimum

    CERN Document Server

    Hamaguchi, K; Gull, T; Ishibashi, K; Pittard, J M; Hillier, D J; Damineli, A; Davidson, K; Nielsen, K E; Kober, G V; Hamaguchi, Kenji; Corcoran, Michael F.; Gull, Theodore; Ishibashi, Kazunori; Pittard, Julian M.; Damineli, Augusto; Davidson, Kris; Nielsen, Krister E.; Kober, Gladys Vieira

    2007-01-01

    We report the results of an X-ray observing campaign on the massive, evolved star Eta Carinae, concentrating on the 2003 X-ray minimum as seen by the XMM-Newton observatory. These are the first spatially-resolved X-ray monitoring observations of the stellar X-ray spectrum during the minimum. The hard X-ray emission, believed to be associated with the collision of Eta Carinae's wind with the wind from a massive companion star, varied strongly in flux on timescales of days, but not significantly on timescales of hours. The lowest X-ray flux in the 2-10 keV band seen by XMM-Newton was only 0.7% of the maximum seen by RXTE just before the X-ray minimum. The slope of the X-ray continuum above 5 keV did not vary in any observation, which suggests that the electron temperature of the hottest plasma associated with the stellar source did not vary significantly at any phase. Through the minimum, the absorption to the stellar source increased by a factor of 5-10 to NH ~3-4E23 cm-2. The thermal Fe XXV emission line show...

  8. X-ray Polarization from High Mass X-ray Binaries

    CERN Document Server

    Kallman, T; Blondin, J

    2015-01-01

    X-ray astronomy allows study of objects which may be associated with compact objects, i.e. neutron stars or black holes, and also may contain strong magnetic fields. Such objects are categorically non-spherical, and likely non-circular when projected on the sky. Polarization allows study of such geoemetric effects, and X-ray polarimetry is likely to become feasible for a significant number of sources in the future. A class of potential targets for future X-ray polarization observations is the high mass X-ray binaries (HMXBs), which consist of a compact object in orbit with an early type star. In this paper ws show that X-ray polarization from HMXBs has a distinct signature which depends on the source inclination and orbital phase. The presence of the X-ray source displaced from the star creates linear polarization even if the primary wind is spherically symmetric whenever the system is viewed away from conjunction. Direct X-rays dilute this polarization whenever the X-ray source is not eclipsed; at mid-eclips...

  9. X-Ray Detector Simulations - Oral Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Tina, Adrienne [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-20

    The free-electron laser at LCLS produces X-Rays that are used in several facilities. This light source is so bright and quick that we are capable of producing movies of objects like proteins. But making these movies would not be possible without a device that can detect the X-Rays and produce images. We need X-Ray cameras. The challenges LCLS faces include the X-Rays’ high repetition rate of 120 Hz, short pulses that can reach 200 femto-seconds, and extreme peak brightness. We need detectors that are compatible with this light source, but before they can be used in the facilities, they must first be characterized. My project was to do just that, by making a computer simulation program. My presentation discusses the individual detectors I simulated, the details of my program, and how my project will help determine which detector is most useful for a specific experiment.

  10. Bone diagnosis by X-ray techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lima, I. [Nuclear Engineering Program/COPPE/UFRJ, P.O. Box 68509, Av. Horacio Macedo, 2030, Sala I-133, Cidade Universitaria, Zip Code: 21941-972 Rio de Janeiro, RJ (Brazil)], E-mail: inaya@lin.ufrj.br; Anjos, M.J. [Nuclear Engineering Program/COPPE/UFRJ, P.O. Box 68509, Av. Horacio Macedo, 2030, Sala I-133, Cidade Universitaria, Zip Code: 21941-972 Rio de Janeiro, RJ (Brazil); Physics Institute, UERJ (Brazil); Farias, M.L.F. [University Hospital, UFRJ (Brazil); Parcegoni, N.; Rosenthal, D. [Biophysics Institute, UFRJ (Brazil); Duarte, M.E.L. [Histologic and Embriology Department, UFRJ (Brazil); Lopes, R.T. [Nuclear Engineering Program/COPPE/UFRJ, P.O. Box 68509, Av. Horacio Macedo, 2030, Sala I-133, Cidade Universitaria, Zip Code: 21941-972 Rio de Janeiro, RJ (Brazil)

    2008-12-15

    In this work, two X-ray techniques used were 3D microcomputed tomography (micro-CT) and X-ray microfluorescence (micro-XRF) in order to investigate the internal structure of the bone samples. Those two techniques work together, e.g. as a complement to each other, to characterize bones structure and composition. Initially, the specimens were used to do the scan procedure in the microcomputer tomography system and the second step consists of doing the X-ray microfluorescence analysis. The results show that both techniques are powerful methods for analyzing, inspecting and characterizing bone samples: they are alternative procedures for examining bone structures and compositions and they are complementary.

  11. Microfabrication of hard x-ray lenses

    DEFF Research Database (Denmark)

    Stöhr, Frederik

    in the vertical and horizontal directions was addressed. A functioning prototype of a 2D silicon objective for use in a bright-field hard-XRM was demonstrated. The results are promising; showing acceptably low aberration and performance close to theoretical expectations. A resolution of 300 nm with 17 keV x......This thesis deals with the development of silicon compound refractive lenses (Si-CRLs) for shaping hard x-ray beams. The CRLs are to be fabricated using state of the art microfabrication techniques. The primary goal of the thesis work is to produce Si-CRLs with considerably increased structure...... intense and wider line beams with narrower waists. The thesis starts with a review of alternative x-ray lenses. Si-CRLs are identified as valuable optical components that allow shaping hard x-rays efficiently and creating beam waists that are clearly in the nanometer range. They stand out...

  12. Filtered fluorescer x-ray detector

    Energy Technology Data Exchange (ETDEWEB)

    Bruns, H.C.; Emig, J.A.; Thoe, R.S.; Springer, P.T.; Hernandez, J.A.

    1995-04-01

    Recently, an instrument capable of measuring x-rays between 8 and 90 keV was conceived to help understand conditions pertaining to pulsed power research. This resulted in the development of a versatile device that would incrementally detect x-rays emitted at predetermined energy bands over this range. To accomplish this, an array of well characterized filter-fluorescer combinations were produced which would allow fluoresced x-rays to be observed by time resolved electro-optical devices. As many as sixteen channels could be utilized with each channel having a corresponding background channel. Upon completion of the device, a three week series of experiments was then successfully carried out.

  13. X-Ray Wakes in Abell 160

    CERN Document Server

    Drake, N; Sakelliou, I; Pinkney, J C; Drake, Nick; Merrifield, Michael R.; Sakelliou, Irini; Pinkney, Jason C.

    2000-01-01

    `Wakes' of X-ray emission have now been detected trailing behind a few (at least seven) elliptical galaxies in clusters. To quantify how widespread this phenomenon is, and what its nature might be, we have obtained a deep (70 ksec) X-ray image of the poor cluster Abell 160 using the ROSAT HRI. Combining the X-ray data with optical positions of confirmed cluster members, and applying a statistic designed to search for wake-like excesses, we confirm that this phenomenon is observed in galaxies in this cluster. The probability that the detections arise from chance is less than 0.0038. Further, the wakes are not randomly distributed in direction, but are preferentially oriented pointing away from the cluster centre. This arrangement can be explained by a simple model in which wakes arise from the stripping of their host galaxies' interstellar media due to ram pressure against the intracluster medium through which they travel.

  14. Contact x-ray microscopy using Asterix

    Science.gov (United States)

    Conti, Aldo; Batani, Dimitri; Botto, Cesare; Masini, Alessandra; Bernardinello, A.; Bortolotto, Fulvia; Moret, M.; Poletti, G.; Piccoli, S.; Cotelli, F.; Lora Lamia Donin, C.; Stead, Anthony D.; Marranca, A.; Eidmann, Klaus; Flora, Francesco; Palladino, Libero; Reale, Lucia

    1997-10-01

    The use of a high energy laser source for soft x-ray contact microscopy is discussed. Several different targets were used and their emission spectra compared. The x-ray emission, inside and outside the Water Window, was characterized in detail by means of many diagnostics, including pin hole and streak cameras. Up to 12 samples holders per shot were exposed thanks to the large x-ray flux and the geometry of the interaction chamber. Images of several biological samples were obtained, including Chlamydomonas and Crethidia green algae, fish and boar sperms and Saccharomyces Cerevisiae yeast cells. A 50 nm resolution was reached on the images of boar sperm. Original information concerning the density of inner structures of Crethidia green algae were obtained.

  15. The X-ray imager on AXO

    DEFF Research Database (Denmark)

    Budtz-Jørgensen, Carl; Kuvvetli, Irfan; Westergaard, Niels Jørgen Stenfeldt

    2001-01-01

    DSRI has initiated a development program of CZT X-ray and gamma-ray detectors employing strip readout techniques. A dramatic improvement of the energy response was found operating the detectors as the so-called drift detectors. For the electronic readout, modern ASIC chips were investigated....... Modular design and the low-power electronics will make large area detectors using the drift strip method feasible. The performance of a prototype CZT system will be presented and discussed. One such detector system has been proposed for future space missions: the X-Ray Imager (XRI) on the Atmospheric X...... thunderstorm system. Additional objective is a detailed mapping of the auroral X-ray and optical emission. XRI comprises a coded mask and a 20 x 40cm(2) CZT detector array covering an energy range from 5 to 200keV....

  16. Electromagnetically induced transparency for x rays

    CERN Document Server

    Buth, Christian; Young, Linda

    2007-01-01

    Electromagnetically induced transparency (EIT) is predicted for x rays in laser-dressed neon gas. The x-ray photoabsorption cross section and polarizability near the Ne K edge are calculated using an ab initio theory suitable for optical strong-field problems. The laser wavelength is tuned close to the transition between 1s^-1 3s and 1s^-1 3p (approximately 800nm). The minimum laser intensity required to observe EIT is of the order of 10^12 W/cm^2. The ab initio results are discussed in terms of an exactly solvable three-level model. This work opens new opportunities for research with ultrafast x-ray sources.

  17. Supernova remnants: the X-ray perspective

    Science.gov (United States)

    Vink, Jacco

    2012-12-01

    Supernova remnants are beautiful astronomical objects that are also of high scientific interest, because they provide insights into supernova explosion mechanisms, and because they are the likely sources of Galactic cosmic rays. X-ray observations are an important means to study these objects. And in particular the advances made in X-ray imaging spectroscopy over the last two decades has greatly increased our knowledge about supernova remnants. It has made it possible to map the products of fresh nucleosynthesis, and resulted in the identification of regions near shock fronts that emit X-ray synchrotron radiation. Since X-ray synchrotron radiation requires 10-100 TeV electrons, which lose their energies rapidly, the study of X-ray synchrotron radiation has revealed those regions where active and rapid particle acceleration is taking place. In this text all the relevant aspects of X-ray emission from supernova remnants are reviewed and put into the context of supernova explosion properties and the physics and evolution of supernova remnants. The first half of this review has a more tutorial style and discusses the basics of supernova remnant physics and X-ray spectroscopy of the hot plasmas they contain. This includes hydrodynamics, shock heating, thermal conduction, radiation processes, non-equilibrium ionization, He-like ion triplet lines, and cosmic ray acceleration. The second half offers a review of the advances made in field of X-ray spectroscopy of supernova remnants during the last 15 year. This period coincides with the availability of X-ray imaging spectrometers. In addition, I discuss the results of high resolution X-ray spectroscopy with the Chandra and XMM-Newton gratings. Although these instruments are not ideal for studying extended sources, they nevertheless provided interesting results for a limited number of remnants. These results provide a glimpse of what may be achieved with future microcalorimeters that will be available on board future X-ray

  18. X-ray optics developments at ESA

    DEFF Research Database (Denmark)

    Bavdaz, M.; Wille, E.; Wallace, K.;

    2013-01-01

    ) in collaboration with research institutions and industry, enabling leading-edge future science missions. Silicon Pore Optics (SPO) [1 to 21] and Slumped Glass Optics (SGO) [22 to 29] are lightweight high performance X-ray optics technologies being developed in Europe, driven by applications in observatory class......Future high energy astrophysics missions will require high performance novel X-ray optics to explore the Universe beyond the limits of the currently operating Chandra and Newton observatories. Innovative optics technologies are therefore being developed and matured by the European Space Agency (ESA...... reflective coatings [30 to 35]. In addition, the progress with the X-ray test facilities and associated beam-lines is discussed [36]. © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only....

  19. The quantum X-ray radiology apparatus

    CERN Document Server

    Hilt, B; Prevot, G

    2000-01-01

    The paper entitled 'New Quantum Detection System for Very Low Dose X-ray Radiology', presented at the talk session, discusses the preliminary data obtained using a new quantum X-ray radiology system with a high-efficiency solid-state detector and highly sensitive electronics, making it possible to reduce significantly the dose administered to a patient in X-ray radiology examinations. The present paper focuses more on the technological aspects of the apparatus, such as the integration of the detector with the two Asics, and the computer system. Namely, it is shown how the computer system calibrates the detection system, acquires the data in real time, and controls the scan parameters and image filtering process.

  20. A Pilot Deep Survey for X-Ray Emission from fuvAGB Stars

    Science.gov (United States)

    Sahai, R.; Sanz-Forcada, J.; Sánchez Contreras, C.; Stute, M.

    2015-09-01

    We report the results of a pilot survey for X-ray emission from a newly discovered class of AGB stars with far-ultraviolet excesses (fuvAGB stars) using XMM-Newton and Chandra. We detected X-ray emission in three of six fuvAGB stars observed—the X-ray fluxes are found to vary in a stochastic or quasi-periodic manner on roughly hour-long timescales, and simultaneous UV observations using the Optical Monitor on XMM for these sources show similar variations in the UV flux. These data, together with previous studies, show that X-ray emission is found only in fuvAGB stars. From modeling the spectra, we find that the observed X-ray luminosities are ˜(0.002-0.2) L⊙ and the X-ray-emitting plasma temperatures are ˜(35-160) × 106 K. The high X-ray temperatures argue against the emission arising in stellar coronae, or directly in an accretion shock, unless it occurs on a WD companion. However, none of the detected objects is a known WD-symbiotic star, suggesting that if WD companions are present, they are relatively cool (<20,000 K). In addition, the high X-ray luminosities specifically argue against emission originating in the coronae of main-sequence companions. We discuss several models for the X-ray emission and its variability and find that the most likely scenario for the origin of the X-ray (and FUV) emission involves accretion activity around a companion star, with confinement by strong magnetic fields associated with the companion and/or an accretion disk around it.

  1. Novel X-ray telescopes for wide-field X-ray monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Hudec, R. [Academy of science of Czech Republic, Ondrejov (Czech Republic); Inneman, A. [Centre for advanced X-ray technologies Reflex sro, Prague (Czech Republic); Pina, L.; Sveda, L. [Czech Technical Univ., Prague (Czech Republic). Faculty of Nuclear Science

    2005-07-15

    We report on fully innovative very wide-field of view X-ray telescopes with high sensitivity as well as large field of view. The prototypes are very promising, allowing the proposals for space projects with very wide-field Lobster-eye X-ray optics to be considered. The novel telescopes will monitor the sky with unprecedented sensitivity and angular resolution of order of 1 arcmin. They are expected to contribute essentially to study and to understand various astrophysical objects such as AGN, SNe, Gamma-ray bursts (GRBs), X-ray flashes (XRFs), galactic binary sources, stars, CVs, X-ray novae, various transient sources, etc. The Lobster optics based X-ray All Sky Monitor is capable to detect around 20 GRBs and 8 XRFs yearly and this will surely significantly contribute to the related science.

  2. Tokamak Spectroscopy for X-Ray Astronomy

    Science.gov (United States)

    Fournier, Kevin B.; Finkenthal, M.; Pacella, D.; May, M. J.; Soukhanovskii, V.; Mattioli, M.; Leigheb, M.; Rice, J. E.

    2000-01-01

    This paper presents the measured x-ray and Extreme Ultraviolet (XUV) spectra of three astrophysically abundant elements (Fe, Ca and Ne) from three different tokamak plasmas. In every case, each spectrum touches on an issue of atomic physics that is important for simulation codes to be used in the analysis of high spectral resolution data from current and future x-ray telescopes. The utility of the tokamak as a laboratory test bed for astrophysical data is demonstrated. Simple models generated with the HULLAC suite of codes demonstrate how the atomic physics issues studied can affect the interpretation of astrophysical data.

  3. European XFEL: Soft X-Ray instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Molodtsov, S. L., E-mail: serguei.molodtsov@xfel.eu [European XFEL GmbH (Germany)

    2011-12-15

    The currently constructed European X-Ray Free Electron Laser (XFEL) will generate new knowledge in almost all the technical and scientific disciplines that are shaping our daily life-including nanotechnology, medicine, pharmaceutics, chemistry, materials science, power engineering and electronics. On 8 January 2009, civil engineering work (tunnels, shafts, halls) has been started at all three construction sites. In this presentation status and parameters of the European XFEL facility and instrumentation as well as planned research applications particularly in the range of soft X-rays are reviewed.

  4. Imaging plates calibration to X-rays

    Science.gov (United States)

    Curcio, A.; Andreoli, P.; Cipriani, M.; Claps, G.; Consoli, F.; Cristofari, G.; De Angelis, R.; Giulietti, D.; Ingenito, F.; Pacella, D.

    2016-05-01

    The growing interest for the Imaging Plates, due to their high sensitivity range and versatility, has induced, in the last years, to detailed characterizations of their response function in different energy ranges and kind of radiation/particles. A calibration of the Imaging Plates BAS-MS, BAS-SR, BAS-TR has been performed at the ENEA-Frascati labs by exploiting the X-ray fluorescence of different targets (Ca, Cu, Pb, Mo, I, Ta) and the radioactivity of a BaCs source, in order to cover the X-ray range between few keV to 80 keV.

  5. Single Particle X-ray Diffractive Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bogan, M J; Benner, W H; Boutet, S; Rohner, U; Frank, M; Seibert, M; Maia, F; Barty, A; Bajt, S; Riot, V; Woods, B; Marchesini, S; Hau-Riege, S P; Svenda, M; Marklund, E; Spiller, E; Hajdu, J; Chapman, H N

    2007-10-01

    In nanotechnology, strategies for the creation and manipulation of nanoparticles in the gas phase are critically important for surface modification and substrate-free characterization. Recent coherent diffractive imaging with intense femtosecond X-ray pulses has verified the capability of single-shot imaging of nanoscale objects at sub-optical resolutions beyond the radiation-induced damage threshold. By intercepting electrospray-generated particles with a single 15 femtosecond soft-X-ray pulse, we demonstrate diffractive imaging of a nanoscale specimen in free flight for the first time, an important step toward imaging uncrystallized biomolecules.

  6. Radiobiological studies using gamma and x rays.

    Energy Technology Data Exchange (ETDEWEB)

    Potter, Charles Augustus; Longley, Susan W.; Scott, Bobby R.; Lin, Yong; Wilder, Julie; Hutt, Julie A.; Padilla, Mabel T.; Gott, Katherine M.

    2013-02-01

    There are approximately 500 self-shielded research irradiators used in various facilities throughout the U.S. These facilities use radioactive sources containing either 137Cs or 60Co for a variety of biological investigations. A report from the National Academy of Sciences[1] described the issues with security of particular radiation sources and the desire for their replacement. The participants in this effort prepared two peer-reviewed publications to document the results of radiobiological studies performed using photons from 320-kV x rays and 137Cs on cell cultures and mice. The effectiveness of X rays was shown to vary with cell type.

  7. Effects of X-Ray Dose On Rhizosphere Studies Using X-Ray Computed Tomography.

    Directory of Open Access Journals (Sweden)

    Susan Zappala

    Full Text Available X-ray Computed Tomography (CT is a non-destructive imaging technique originally designed for diagnostic medicine, which was adopted for rhizosphere and soil science applications in the early 1980s. X-ray CT enables researchers to simultaneously visualise and quantify the heterogeneous soil matrix of mineral grains, organic matter, air-filled pores and water-filled pores. Additionally, X-ray CT allows visualisation of plant roots in situ without the need for traditional invasive methods such as root washing. However, one routinely unreported aspect of X-ray CT is the potential effect of X-ray dose on the soil-borne microorganisms and plants in rhizosphere investigations. Here we aimed to i highlight the need for more consistent reporting of X-ray CT parameters for dose to sample, ii to provide an overview of previously reported impacts of X-rays on soil microorganisms and plant roots and iii present new data investigating the response of plant roots and microbial communities to X-ray exposure. Fewer than 5% of the 126 publications included in the literature review contained sufficient information to calculate dose and only 2.4% of the publications explicitly state an estimate of dose received by each sample. We conducted a study involving rice roots growing in soil, observing no significant difference between the numbers of root tips, root volume and total root length in scanned versus unscanned samples. In parallel, a soil microbe experiment scanning samples over a total of 24 weeks observed no significant difference between the scanned and unscanned microbial biomass values. We conclude from the literature review and our own experiments that X-ray CT does not impact plant growth or soil microbial populations when employing a low level of dose (<30 Gy. However, the call for higher throughput X-ray CT means that doses that biological samples receive are likely to increase and thus should be closely monitored.

  8. Differential phase contrast X-ray imaging system and components

    Science.gov (United States)

    Stutman, Daniel; Finkenthal, Michael

    2014-07-01

    A differential phase contrast X-ray imaging system includes an X-ray illumination system, a beam splitter arranged in an optical path of the X-ray illumination system, and a detection system arranged in an optical path to detect X-rays after passing through the beam splitter.

  9. Differential phase contrast X-ray imaging system and components

    Energy Technology Data Exchange (ETDEWEB)

    Stutman, Daniel; Finkenthal, Michael

    2017-01-31

    A differential phase contrast X-ray imaging system includes an X-ray illumination system, a beam splitter arranged in an optical path of the X-ray illumination system, and a detection system arranged in an optical path to detect X-rays after passing through the beam splitter.

  10. Soft X-ray emission of nearby galaxy M81

    Institute of Scientific and Technical Information of China (English)

    苏旸; 毕红光; 李启斌

    1997-01-01

    The pointed observations of NGC3077 are analyzed by position sensitive proportional counter (PSPC) on board the ROSAT satellite on 1991-04-18, 1991, finding out that the X-ray emission range of M81 galaxy has, in the softer and more sensitive ROSAT PSPC band (0. 2-2. 4 keV), extended by 40% larger than ever observed by image proportional counter (IPC) on board the Einstein satellite, which shows that M81 galaxy has a larger X-ray corona. And by the aid of the timing analysis, it is concluded that M81 nucleus has no variabilities on time scale of a few minutes; hence the possibility of M81 nucleus having the marginal variability over time scale of about 2 min that Fabbiano (1988) found from the Einstein IPC observation is ruled out.

  11. X-ray follow up observations of new IGRs

    CERN Document Server

    Rodriguez, Jerome; Tomsick, John A

    2011-01-01

    Since the launch of INTEGRAL in 2002, about 300 new sources have been discovered. Understanding the nature of these objects is of prime importance for many aspects of astrophysics, such as the evolution of stars, population of sources (Galactic and extra-Galactic), and ultimately the physics powering them. However, their nature cannot be established from the soft gamma-ray observations. The first step towards unveiling the nature of those sources is to refine their X-ray position, in order to finally find counterparts at other wavelengths. X-ray spectra are also of prime importance to obtain clues on the nature of the objects. Since the discovery of the first IGR in 2003, our group has been active in several aspects of these studies. Here, we present the main results we have obtained through 7 years of multi-instrumental (Chandra, XMM, Swift, RXTE) campaigns.

  12. X-ray shout echoing through space

    Science.gov (United States)

    2004-01-01

    a flash of X-rays hi-res Size hi-res: 3991 Kb Credits: ESA, S. Vaughan (University of Leicester) EPIC camera shows the expanding rings caused by a flash of X-rays XMM-Newton's X-ray EPIC camera shows the expanding rings caused by a flash of X-rays scattered by dust in our Galaxy. The X-rays were produced by a powerful gamma-ray burst that took place on 3 December 2003. The slowly fading afterglow of the gamma-ray burst is at the centre of the expanding rings. Other, unrelated, X-ray sources can also be seen. The time since the gamma-ray explosion is shown in each panel in hours. At their largest size, the rings would appear in the sky about five times smaller than the full moon. a flash of X-rays hi-res Size hi-res: 2153 Kb Credits: ESA, S. Vaughan (University of Leicester) EPIC camera shows the expanding rings caused by a flash of X-rays (Please choose "hi-res" version for animation) XMM-Newton's X-ray EPIC camera shows the expanding rings caused by a flash of X-rays scattered by dust in our Galaxy. The X-rays were produced by a powerful gamma-ray burst that took place on 3 December 2003. The slowly fading afterglow of the gamma-ray burst is at the centre of the expanding rings. Other, unrelated, X-ray sources can also be seen. The time since the gamma-ray explosion is shown in each panel in seconds. At their largest size, the rings would appear in the sky about five times smaller than the full moon. This echo forms when the powerful radiation of a gamma-ray burst, coming from far away, crosses a slab of dust in our Galaxy and is scattered by it, like the beam of a lighthouse in clouds. Using the expanding rings to precisely pin-point the location of this dust, astronomers can identify places where new stars and planets are likely to form. On 3 December 2003 ESA's observatory, Integral, detected a burst of gamma rays, lasting about 30 seconds, from the direction of a distant galaxy. Within minutes of the detection, thanks to a sophisticated alert network, many

  13. [Rupture of an intracerebral dermoid cyst. Apropos of a case: x-ray computed tomographic aspects].

    Science.gov (United States)

    Baudrillard, J C; Scherpereel, B; Rousseaux, P; Lerais, J M; Toubas, O; Auquier, F; Guyot, J F; Lacour, P Y

    1986-02-01

    We report the C.T. findings of a dermoid cyst communicating with ventricular system and ruptured in the subarachnoid space. A fat-fluid level and calcifications were present on the plain skull X rays.

  14. Luminous Binary Supersoft X-Ray Sources

    Science.gov (United States)

    Oliversen, Ronald J. (Technical Monitor); DiStefano, Roseanne

    2005-01-01

    One of the key accomplishments of the two preceding years was our development of an algorithm to select SSSs in external galaxies which have been observed by Chandra or XMM-Newton. By applying this algorithm to data from a number of galaxies, we discovered an extension of the class of SSSs to sources that are somewhat harder (100 - 300 eV, instead of tens of eV), but which are nevertheless much softer than canonical X-ray sources. We call these new sources quasisoft sources (QSSs). During this past year, we have built on and extended this work. We have (1) continued to identify SSSs and QSSs in external galaxies, (2) worked on models for the sources and find that black hole models seem promising for a subset of them, and (3) have studied individual systems, especially M101-ULX1. This special system has been observed as an SSS in its high &ate, with a luminosity in excess of 10(exp 41) erg/s. It has also been observed as a QSS when it is less luminous, and as a hard source in its low state. It is one of the best candidates to be an accreting intermediate-mass black hole. We have several papers in preparation. Below we list papers which are complete, including only new work and papers whose status has changed (e.g., been accepted for publication) since our last report. In addition, our work on QSSs has received some publicity. It was the subject of a Chandra press release and was picked up by several media outlets.

  15. Precision Timing of Two Anomalous X-Ray Pulsars.

    Science.gov (United States)

    Kaspi; Chakrabarty; Steinberger

    1999-11-01

    We report on long-term X-ray timing of two anomalous X-ray pulsars, 1RXS J170849.0-400910 and 1E 2259+586, using the Rossi X-Ray Timing Explorer. In monthly observations made over 1.4 and 2.6 yr for the two pulsars, respectively, we have obtained phase-coherent timing solutions which imply that these objects have been rotating with great stability throughout the course of our observations. For 1RXS J170849.0-400910, we find a rotation frequency of 0.0909169331(5) Hz and frequency derivative -15.687&parl0;4&parr0;x10-14 Hz s-1 for epoch MJD 51215.931. For 1E 2259+586, we find a rotation frequency of 0.1432880613(2) Hz and frequency derivative -1.0026&parl0;7&parr0;x10-14 Hz s-1 for epoch MJD 51195.583. The rms phase residuals from these simple models are only approximately 0.01 cycles for both sources. We show that the frequency derivative for 1E 2259+586 is inconsistent with that inferred from incoherent frequency observations made over the last 20 yr. Our observations are consistent with the magnetar hypothesis and make binary accretion scenarios appear unlikely.

  16. Reionization by UV or X-ray sources

    CERN Document Server

    Baek, S; Di Matteo, P; Revaz, Y; Combes, F

    2010-01-01

    We present simulations of the 21-cm signal during the Epoch of reionization. We focus on modeling properly the absorption regime in the presence of inhomogeneous Wouthuysen-Field effect and X-ray heating. We have run radiative transfer simulations for three bands in the source spectrum (Lyman, UV and X-ray) in order to fully account for these processes. We find that the brightness temperature fluctuation of the 21 cm signal has an amplitude larger than 100 mK during the early reionization, up to 10 times higher than the typical amplitude of a few 10 mK obtained during the later emission phase. More importantly, we find that even a rather high contribution from QSO-like sources only damps the absorption regime without erasing it. Heating the IGM with X-ray takes time. Our results show that observations of the early reionization will probably benefit from a higher signal-to-noise value than during later stages. Analyzing the statistical properties of the signal (power spectrum and PDF) we found three diagnostic...

  17. X-ray burst-induced spectral variability in 4U 1728-34

    Science.gov (United States)

    Kajava, J. J. E.; Sánchez-Fernández, C.; Kuulkers, E.; Poutanen, J.

    2017-03-01

    Aims: INTEGRAL has been monitoring the Galactic center region for more than a decade. Over this time it has detected hundreds of type-I X-ray bursts from the neutron star low-mass X-ray binary 4U 1728-34, also known as the slow burster. Our aim is to study the connection between the persistent X-ray spectra and the X-ray burst spectra in a broad spectral range. Methods: We performed spectral modeling of the persistent emission and the X-ray burst emission of 4U 1728-34 using data from the INTEGRAL JEM-X and IBIS/ISGRI instruments. Results: We constructed a hardness intensity diagram to track spectral state variations. In the soft state, the energy spectra are characterized by two thermal components likely coming from the accretion disc and the boundary/spreading layer, together with a weak hard X-ray tail that we detect in 4U 1728-34 for the first time in the 40 to 80 keV range. In the hard state, the source is detected up to 200 keV and the spectrum can be described by a thermal Comptonization model plus an additional component: either a powerlaw tail or reflection. By stacking 123 X-ray bursts in the hard state, we detect emission up to 80 keV during the X-ray bursts. We find that during the bursts the emission above 40 keV decreases by a factor of approximately three with respect to the persistent emission level. Conclusions: Our results suggest that the enhanced X-ray burst emission changes the spectral properties of the accretion disc in the hard state. The likely cause is an X-ray burst induced cooling of the electrons in the inner hot flow near the neutron star.

  18. Chest Pain

    Directory of Open Access Journals (Sweden)

    Samad Shams-Vahdati

    2014-03-01

    Full Text Available Introduction: Acute chest pain is an important and frequently occurring symptom in patients. Chest pain is often a sign of ischemic heart disease. Associated findings of electrocardiograph (ECG are rather heterogeneous, and traditional cardiac biomarkers such as Creatine Kinase-MB (CK-MB suffer from low cardiac specificity and sensitivity. In this study cost effectiveness of cardiac biomarkers single quantitative measurement was examined.Methods: The present descriptive-analytic study conducted on patients who were asked for troponin I and CK-MB. All patients who referred to Emergency unit of Tabriz Imam Reza educational-medical center during January 2012 to July the 2013 were included in study. All patients included in the study were documented in terms of age, sex, working shift of referring, main complaint of patient, symptoms in referring, ECG findings, and results of troponin I and CK-MB tests.Results: In this study, 2900 patients were studied including 1440 (49.7% males and 1460 (50.3% females. Mean age of patients was 62.91 (SD=14.36. Of all patients 1880 (64.8% of patients referred during 8 a.m. to 8 p.m. and 1020 (35.2% patients were referred during 8 p.m. to 8 a.m. The sensitivity of cardiac biomarkers’ test in diagnosing Acute Coronary Syndrome (ACS disease was calculated as 44.8% and its specificity was 86.6%. For diagnosing Acute Myocardial Infarction (AMI, sensitivity of cardiac biomarkers’ test was 72.2% and its specificity was 86%. None of patients who were finally underwent unstable angina diagnosis showed increase in cardiac enzymes.Conclusion: In conclusion, cardiac biomarkers can be used for screening acute chest pains, also cost effectiveness of cardiac biomarkers, appropriate specificity and sensitivity can guarantee their usefulness in emergency room.

  19. Polymer Compund Refractive Lenses for Hard X-ray Nanofocusing

    OpenAIRE

    Krywka, Christina; Last, Arndt; Marschall, Felix; Markus, Otto; Georgi, Sebastian; Mueller, Martin; Mohr, Jürgen

    2016-01-01

    Compound refractive lenses fabricated out of SU-8 negative photoresist have been used to generate a nanofocused, i.e. sub-μm sized X-ray focal spot at an X-ray nanodiffraction setup. X-ray microscopy and X-ray diffraction techniques have conceptually different demands on nanofocusing optical elements and so with the application of X-ray nanodiffraction in mind, this paper presents the results of an initial characterization of polymer lenses used as primary focusin...

  20. An X-ray and optical study of the ultracompact X-ray binary A 1246-58

    NARCIS (Netherlands)

    in 't Zand, J. J. M.; Bassa, C. G.; Keek, L.; Verbunt, F.; Mendez, M.; Markwardt, C. B.; Jonker, P.G.

    2008-01-01

    Results are discussed of an X-ray and optical observation campaign of the low-mass X-ray binary A 1246-58 performed with instruments on Satellite per Astronomia X ("BeppoSAX"), the Rossi X-ray Timing Explorer (RXTE), the X-ray Multi-mirror Mission ("XMM-Newton"), the Swift mission, and the Very Larg