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Sample records for rhic snake coils

  1. Observations of Snake Resonance in RHIC

    CERN Document Server

    Bai, Mei; Lee, Shyh-Yuan; Lin, Fanglei; MacKay, William; Ptitsyn, Vadim; Roser, Thomas; Tepikian, Steven

    2005-01-01

    Siberian snakes now become essential in the polarized proton acceleration. With proper configuration of Siberian snakes, the spin precession tune of the beam becomes $\\frac{1}{2}$ which avoids all the spin depolarizing resonance. However, the enhancement of the perturbations on the spin motion can still occur when the betatron tune is near some low order fractional numbers, called snake resonances, and the beam can be depolarized when passing through the resonance. The snake resonances have been confirmed in the spin tracking calculations, and observed in RHIC with polarized proton beam. Equipped with two full Siberian snakes in each ring, RHIC provides us a perfect facility for snake resonance studies. This paper presents latest experimental results. New insights are also discussed.

  2. Helical spin rotators and snakes for RHIC

    International Nuclear Information System (INIS)

    Ptitsin, V.I.; Shatunov, Yu.M.; Peggs, S.

    1995-01-01

    The RHIC collider, now under construction at BNL, will have the possibility of polarized proton-proton collisions up to a beam energy of 250 Gev. Polarized proton beams of such high energy can be only obtained with the use of siberian snakes, a special kind of spin rotator that rotates the particle spin by 180 degree around an axis lying in the horizontal plane. Siberian snakes help to preserve the beam polarization while numerous spin depolarizing resonances are crossed, during acceleration. In order to collide longitudinally polarized beams, it is also planned to install spin rotators around two interaction regions. This paper discusses snake and spin rotator designs based on sequences of four helical magnets. The schemes that were chosen to be applied at RHIC are presented

  3. FITTING HELICAL SNAKE AND ROTATOR FIELD STRENGTH MEASUREMENTS IN RHIC

    International Nuclear Information System (INIS)

    RANJBAR, V.; LUCCIO, A.U.; MACKAY, W.W.; TSOUPAS, N.

    2001-01-01

    We examined recent multi-pole measurements for the helical snakes and rotators in RHIC to generate a full field map. Since multi-pole measurements yield real field values for B, field components we developed a unique technique to evaluate the full fields using a traditional finite element analysis software [1]. From these measurements we employed SNIG [2] to generate orbit and Spin plots. From orbit values we generated a transfer matrix for the first snake

  4. Half-length model of a Siberian Snake magnet for RHIC

    CERN Document Server

    Okamura, M; Kawaguchi, T; Katayama, T; Jain, A; Muratore, J; Morgan, G; Willen, E

    2000-01-01

    For the Relativistic Heavy Ion Collider (RHIC) Spin Project, super-conducting helical dipole magnets are being constructed. These magnets will be used in 'Siberian Snakes' and 'Spin Rotators', which manipulate spin direction of proton beams in RHIC. The dipole field in these magnets rotates 360 deg. and is required to reach a magnetic field strength of more than 4.0 T. The bore radius of the coils and the magnetic length of the magnets are 50 and 2400 mm, respectively. To ascertain the performance of these magnets, which are built using a new 'coil in a slot' technique, a half-length model has been fabricated and tested. The quench performance, field uniformity and rotation angle have been investigated. The measured values in the model magnet agreed well with field calculations. These results demonstrate the adequacy of the fabrication method adopted in the model magnet. (authors)

  5. Numerical studies of Siberian snakes and spin rotators for RHIC

    International Nuclear Information System (INIS)

    Luccio, A.

    1995-01-01

    For the program of polarized protons in RHIC, two Siberian snakes and four spin rotators per ring will be used. The Snakes will produce a complete spin flip. Spin Rotators, in pairs, will rotate the spin from the vertical direction to the horizontal plane at a given insertion, and back to the vertical after the insertion. Snakes, 180 degrees apart and with their axis of spin precession at 90 degrees to each other, are an effective means to avoid depolarization of the proton beam in traversing resonances. Classical snakes and rotators are made with magnetic solenoids or with a sequence of magnetic dipoles with fields alternately directed in the radial and vertical direction. Another possibility is to use helical magnets, essentially twisted dipoles, in which the field, transverse the axis of the magnet, continuously rotates as the particles proceed along it. After some comparative studies, the authors decided to adopt for RHIC an elegant solution with four helical magnets both for the snakes and the rotators proposed by Shatunov and Ptitsin. In order to simplify the construction of the magnets and to minimize cost, four identical super conducting helical modules will be used for each device. Snakes will be built with four right-handed helices. Spin rotators with two right-handed and two left-handed helices. The maximum field will be limited to 4 Tesla. While small bore helical undulators have been built for free electron lasers, large super conducting helical magnets have not been built yet. In spite of this difficulty, this choice is dictated by some distinctive advantages of helical over more conventional transverse snakes/rotators: (i) the devices are modular, they can be built with arrangements of identical modules, (ii) the maximum orbit excursion in the magnet is smaller, (iii) orbit excursion is independent from the separation between adjacent magnets, (iv) they allow an easier control of the spin rotation and the orientation of the spin precession axis

  6. The new conceptual design of snakes and spin rotators in RHIC

    International Nuclear Information System (INIS)

    Lee, S.Y.; Courant, E.D.

    1990-01-01

    We discuss the generalized snake configurations, which offers either the advantages of shorter total snake length and smaller horizontal orbit displacement in the compact configuration or the dual functions of a snake and a 90 degree spin rotation for the helicity state. The generalized snake is then applied to the polarized proton collision in RHIC. The possible schemes of obtaining high luminosity are discussed

  7. OVERVIEW OF THE RHIC INSERTION REGION, SEXTUPOLE, AND SNAKE POWER SUPPLY SYSTEMS

    International Nuclear Information System (INIS)

    BRUNO, D.; ENG, W.; GANETIS, G.; LAMBIASE, R.F.; SANDBERG, J.

    2001-01-01

    The Relativistic Heavy Ion Collider (RHIC) was commissioned in 1999 and 2000. RHIC requires power supplies to supply currents to highly inductive superconducting magnets. The RHIC Insertion Region (IR) contains many shunt power supplies to trim the current of different magnet elements in a large superconducting magnet circuit. There are a total of 237 Insertion Region power supplies in both RHIC rings. RHIC also requires sextupole power supplies. One sextupole power supply is connected across 12 sextupole magnets. There are a total of 24 sextupole power supplies in both rings. Snake magnets are also a part of the RHIC ring, and these snake magnets also require power supplies. There shall be a total of 24 snake power supplies in both rings. Power supply technology, connections, control systems and interfacing with the Quench Protection System will be presented

  8. Re-visiting RHIC snakes: OPERA fields, n0 dance

    Energy Technology Data Exchange (ETDEWEB)

    Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gupta, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-09-22

    In this Tech. Note RHIC snakes and stable spin direction $\\vector{n}$0(s) are re-visited, based on OPERA-computed field maps of the former. The numerical simulations so undertaken provide various outcomes regarding RHIC optics and spin dynamics, in relation with orbital and focusing effects resulting from the use of this realistic 3-D representation of the snakes.

  9. New coil end design for the RHIC Arc dipole

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, G.H.; Morgillo, A.; Power, K.; Thompson, P.

    1994-06-01

    To simplify production, the number of parts in the ends, about 64 in each coil end, was reduced by using thicker spacers between the turns, to about 23. A new computer program was written which gives a description of each turn closely resembling the turn as made. The output of this program is processed by newly written computer programs which change the parts descriptions into forms which are used by a computer-controlled, 5-axis milling machine. The solid spacers replace spacers assembled from laminations and improve the fit as well. The parts will be molded during production. The calculated harmonic content of the ends is compared with measurements on the first magnets built with the new ends.

  10. New coil end design for the RHIC Arc dipole

    International Nuclear Information System (INIS)

    Morgan, G.H.; Morgillo, A.; Power, K.; Thompson, P.

    1994-01-01

    To simplify production, the number of parts in the ends, about 64 in each coil end, was reduced by using thicker spacers between the turns, to about 23. A new computer program was written which gives a description of each turn closely resembling the turn as made. The output of this program is processed by newly written computer programs which change the parts descriptions into forms which are used by a computer-controlled, 5-axis milling machine. The solid spacers replace spacers assembled from laminations and improve the fit as well. The parts will be molded during production. The calculated harmonic content of the ends is compared with measurements on the first magnets built with the new ends

  11. Snakes! Snakes! Snakes!

    Science.gov (United States)

    Nature Naturally, 1983

    1983-01-01

    Designed for students in grades 4-6, the teaching unit presents illustrations and facts about snakes. Topics include common snakes found in the United States, how snakes eat, how snakes shed their skin, poisonous snakes, the Eastern Indigo snake, and the anatomy of a snake. A student page includes a crossword puzzle and surprising snake facts. A…

  12. Polarized Proton Collisions at RHIC

    CERN Document Server

    Bai, Mei; Alekseev, Igor G; Alessi, James; Beebe-Wang, Joanne; Blaskiewicz, Michael; Bravar, Alessandro; Brennan, Joseph M; Bruno, Donald; Bunce, Gerry; Butler, John J; Cameron, Peter; Connolly, Roger; De Long, Joseph; Drees, Angelika; Fischer, Wolfram; Ganetis, George; Gardner, Chris J; Glenn, Joseph; Hayes, Thomas; Hseuh Hsiao Chaun; Huang, Haixin; Ingrassia, Peter; Iriso, Ubaldo; Laster, Jonathan S; Lee, Roger C; Luccio, Alfredo U; Luo, Yun; MacKay, William W; Makdisi, Yousef; Marr, Gregory J; Marusic, Al; McIntyre, Gary; Michnoff, Robert; Montag, Christoph; Morris, John; Nicoletti, Tony; Oddo, Peter; Oerter, Brian; Osamu, Jinnouchi; Pilat, Fulvia Caterina; Ptitsyn, Vadim; Roser, Thomas; Satogata, Todd; Smith, Kevin T; Svirida, Dima; Tepikian, Steven; Tomas, Rogelio; Trbojevic, Dejan; Tsoupas, Nicholaos; Tuozzolo, Joseph; Vetter, Kurt; Wilinski, Michelle; Zaltsman, Alex; Zelenski, Anatoli; Zeno, Keith; Zhang, S Y

    2005-01-01

    The Relativistic Heavy Ion Collider~(RHIC) provides not only collisions of ions but also collisions of polarized protons. In a circular accelerator, the polarization of polarized proton beam can be partially or fully lost when a spin depolarizing resonance is encountered. To preserve the beam polarization during acceleration, two full Siberian snakes were employed in RHIC to avoid depolarizing resonances. In 2003, polarized proton beams were accelerated to 100~GeV and collided in RHIC. Beams were brought into collisions with longitudinal polarization at the experiments STAR and PHENIX by using spin rotators. RHIC polarized proton run experience demonstrates that optimizing polarization transmission efficiency and improving luminosity performance are significant challenges. Currently, the luminosity lifetime in RHIC is limited by the beam-beam effect. The current state of RHIC polarized proton program, including its dedicated physics run in 2005 and efforts to optimize luminosity production in beam-beam limite...

  13. Polarized proton parameters for the 2015 PP-on-Au setup in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, C. J. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-08-25

    Values are given for RHIC circumference shifts due to snakes for various situations. Relevant parameters are tabulated for polarized protons (PP) in the booster and in AGS and RHIC for PP-on-Au stores.

  14. Polarized proton parameters for the 2015 PP-on-Aluminum setup in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, C. J. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-10-02

    Values are given for RHIC circumference shifts due to snakes for various situations. Relevant parameters are tabulated for polarized protons (PP) in the booster and in AGS and RHIC for PP-on-Aluminum stores.

  15. FIRST POLARIZED PROTON COLLISIONS AT RHIC

    International Nuclear Information System (INIS)

    ROSER, T.; AHRENS, L.; ALESSI, J.; BAI, M.; BEEBE-WANG, J.; BRENNAN, J.M.; BROWN, K.A.; BUNCE, G.; CAMERON, P.; COURANT, E.D.; DREES, A.; FISCHER, W.; FLILLER, R. III; GLENN, W.; HUANG, H.; LUCCIO, A.U.; MACKAY, W.W.; MAKDISI, Y.; MONTAG, C.; PILAT, F.; PTITSYN, V.; SATOGATA, T.

    2002-01-01

    We successfully injected polarized protons in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. Each snake consists of four helical superconducting dipoles which rotate the polarization by 180 o about a horizontal axis. This is the first time that polarized protons have been accelerated to 100 GeV

  16. RHIC spin physics

    International Nuclear Information System (INIS)

    Bunce, G.

    1994-01-01

    The physics potential of colliding beams of protons, polarized either longitudinally or transversely, at RHIC is remarkable. A luminosity of L = 2 x 10 32 cm -2 with 70% polarized beams will be available with up to 250 GeV energy in each beam. The proposal to collide polarized protons in RHIC was submitted in August 1992 and approved in October 1993. We have funding for R ampersand D on Siberian Snakes, so that RHIC will be able to accelerate polarized protons early in its program. The expected date of the first heavy ion collisions is 1999. The spin physics program includes measurement of gluon and sea quark polarization in the longitudinally polarized proton, measurement and then application of parity violation in W and Z production, measurement of hard scattering parton-parton asymmetries, and quark polarization or transversity in transversely polarized protons. Single spin asymmetries allow sensitive searches for parity violation (longitudinal polarization), and correlations between quark spin and gluons (transverse). Probes include direct photons (to P T = 20 GeV/c), jets (to P T > 50 GeV/c), Drell-Yan pairs to M ell ell = 9 GeV, W ± , Z. This program is described in our Particle World paper. Here we will emphasize the new information included in our Update, given to the Brookhaven PAC this September

  17. RHIC spin physics

    International Nuclear Information System (INIS)

    Bunce, G.

    1993-01-01

    The physics potential of colliding beams of protons, polarized either longitudinally or transversely, at RHIC is remarkable. A luminosity of L = 2 x 10 32 cm -2 sec -1 with 70% polarized beams will be available with up to 250 GeV energy in each beam. The proposal to collide polarized protons in RHIC was submitted in August 1992 and approved in October 1993, just after this workshop. The collaboration has been encouraged to complete R ampersand D on Siberian Snakes, so that RHIC will be able to accelerate polarized protons early in its program. The expected date of the first heavy ion collisions is 1999. The spin physics program includes measurement of gluon and sea quark polarization in the longitudinally polarized proton, measurement and then application of parity violation in W and Z production, measurement of hard scattering parton-parton asymmetries, and quark polarization or transversity in transversely polarized protons. Single spin asymmetries allow sensitive searches for parity violation (longitudinal polarization), and correlations between quark spin and gluons (transverse). Probes include direct photons (to p T = 20 GeV/c), jets (to p T > 50 GeV/c), Drell-Yan pairs (to m ll = 9 GeV), W +/- , Z. Here, the collaboration emphasizes the new information included in the Update, given to the Brookhaven PAC this September

  18. Polarized proton acceleration program at the AGS and RHIC

    International Nuclear Information System (INIS)

    Lee, Y.Y.

    1995-01-01

    Presented is an overview of the program for acceleration of polarized protons in the AGS and their injection into the RHIC collider. The problem of depolarizing resonances in strong focusing circulator accelerators is discussed. The intrinsic resonances are jumped over by the fast tune jump, and a partial Siberian Snake is used to compensate for over forty imperfection resonances in the AGS. Two sets of full Siberian Snake and spin rotators will be employed in RHIC

  19. Polarized proton beam for eRHIC

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    RHIC has provided polarized proton collisions from 31 GeV to 255 GeV in the past decade. To preserve polarization through numerous depolarizing resonances through the whole accelerator chain, harmonic orbit correction, partial snakes, horizontal tune jump system and full snakes have been used. In addition, close attentions have been paid to betatron tune control, orbit control and beam line alignment. The polarization of 60% at 255 GeV has been delivered to experiments with 1.8×1011 bunch intensity. For the eRHIC era, the beam brightness has to be maintained to reach the desired luminosity. Since we only have one hadron ring in the eRHIC era, existing spin rotator and snakes can be converted to six snake configuration for one hadron ring. With properly arranged six snakes, the polarization can be maintained at 70% at 250 GeV. This paper summarizes the effort and plan to reach high polarization with small emittance for eRHIC.

  20. Spin tune dependence on closed orbit in RHIC

    International Nuclear Information System (INIS)

    Ptitsyn, V.; Bai, M.; Roser, T.

    2010-01-01

    Polarized proton beams are accelerated in RHIC to 250 GeV energy with the help of Siberian Snakes. The pair of Siberian Snakes in each RHIC ring holds the design spin tune at 1/2 to avoid polarization loss during acceleration. However, in the presence of closed orbit errors, the actual spin tune can be shifted away from the exact 1/2 value. It leads to a corresponding shift of locations of higher-order ('snake') resonances and limits the available betatron tune space. The largest closed orbit effect on the spin tune comes from the horizontal orbit angle between the two snakes. During RHIC Run in 2009 dedicated measurements with polarized proton beams were taken to verify the dependence of the spin tune on the local orbits at the Snakes. The experimental results are presented along with the comparison with analytical predictions.

  1. RHIC spin program

    International Nuclear Information System (INIS)

    Bunce, G.

    1995-01-01

    Colliding beams of high energy polarized protons at RHIC is an excellent way to probe the polarization of gluons, u and d quarks in a polarized proton. RHIC is the Relativistic Heavy Ion Collider being built now at Brookhaven in the ISABELLE tunnel. It is designed to collide gold ions on gold ions at 100 GeV/nucleon. Its goal is to discover the quark-gluon plasma, and the first collisions are expected in March, 1999. RHIC will also make an ideal polarized proton collider with high luminosity and 250 GeV x 250 GeV collisions. The RHIC spin physics program is: (1) Use well-understood perturbative QCD probes to study non-perturbative confining dynamics in QCD. We will measure - gluon and sea quark polarization in a polarized proton, polarization of quarks in a transversely polarized proton. (2) Look for additional surprises using the first high energy polarized proton collider. We will - look for the expected maximal parity violation in W and Z boson production, - search for parity violation in other processes, - test parton models with spin. This lecture is organized around a few of the key ideas: Siberian Snakes--What are they? High energy proton-proton collisions are scatters of quarks and leptons, at high x, a polarized proton beam is a beam of polarized u quarks, quark and gluon collisions are very sensitive to spin. We will discuss two reactions: how direct photon production measures gluon polarization, and how W + boson production measures u and d quark polarization

  2. RHIC spin program

    Energy Technology Data Exchange (ETDEWEB)

    Bunce, G.

    1995-12-31

    Colliding beams of high energy polarized protons at RHIC is an excellent way to probe the polarization of gluons, u and d quarks in a polarized proton. RHIC is the Relativistic Heavy Ion Collider being built now at Brookhaven in the ISABELLE tunnel. It is designed to collide gold ions on gold ions at 100 GeV/nucleon. Its goal is to discover the quark-gluon plasma, and the first collisions are expected in March, 1999. RHIC will also make an ideal polarized proton collider with high luminosity and 250 GeV x 250 GeV collisions. The RHIC spin physics program is: (1) Use well-understood perturbative QCD probes to study non-perturbative confining dynamics in QCD. We will measure - gluon and sea quark polarization in a polarized proton, polarization of quarks in a transversely polarized proton. (2) Look for additional surprises using the first high energy polarized proton collider. We will - look for the expected maximal parity violation in W and Z boson production, - search for parity violation in other processes, - test parton models with spin. This lecture is organized around a few of the key ideas: Siberian Snakes--What are they? High energy proton-proton collisions are scatters of quarks and leptons, at high x, a polarized proton beam is a beam of polarized u quarks, quark and gluon collisions are very sensitive to spin. We will discuss two reactions: how direct photon production measures gluon polarization, and how W{sup +} boson production measures u and d quark polarization.

  3. Prospects for polarization at RHIC and SSC

    International Nuclear Information System (INIS)

    Lee, S.Y.

    1991-01-01

    In low to medium energy accelerators, betatron tune jumps and vertical orbit harmonic correction methods have been used to overcome the intrinsic and imperfection resonances. At high energy accelerators, snakes are needed to preserve polarization. We analyze the effects of snake resonances, snake imperfections overlapping resonances on the spin depolarization. We discuss also results of recent snake experiments at the IUCF Cooler Ring. The snake can overcome various kinds of spin depolarization resonances. These experiments pointed out further that partial snake can be used to cure the imperfection resonances in low to medium energy accelerators. We also examine various snake designs. A new generalized snake concept allows for two possible configurations. The compact configuration offers the advantages of shorter total snake length and smaller horizontal orbit displacement. The split snake configuration allows for dual functions of a snake and a 90 degree spin rotator at the mid-section of the snake, which provides helicity state collisions. The requirements for obtaining high luminosity polarized protons at high energy colliders, such as RHIC and SSC, are reviewed

  4. High luminosity polarized proton collisions at RHIC

    International Nuclear Information System (INIS)

    Roser, T.

    2001-01-01

    The Brookhaven Relativistic Heavy Ion Collider (RHIC) provides the unique opportunity to collide polarized proton beams at a center-of-mass energy of up to 500 GeV and luminosities of up to 2 x 10 32 cm -2 s -1 . Such high luminosity and high energy polarized proton collisions will open up the possibility of studying spin effects in hard processes. However, the acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. After successful operation of RHIC with gold beams polarized protons from the AGS have been successfully injected into RHIC and accelerated using a full Siberian snakes built from four superconducting helical dipoles. A new high energy proton polarimeter was also successfully commissioned. Operation with two snakes per RHIC ring is planned for next year

  5. ACCELERATION OF POLARIZED PROTONS AT RHIC

    International Nuclear Information System (INIS)

    HUANG, H.

    2002-01-01

    Relativistic Heavy Ion Collider (RHIC) ended its second year of operation in January 2002 with five weeks of polarized proton collisions. Polarized protons were successfully injected in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. This is the first time that polarized protons have been accelerated to 100 GeV. The machine performance and accomplishments during the polarized proton run will be reviewed. The plans for the next polarized proton run will be outlined

  6. Polarization simulations in the RHIC run 15 lattice

    Energy Technology Data Exchange (ETDEWEB)

    Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Luo, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; White, S. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2015-05-03

    RHIC polarized proton Run 15 uses a new acceleration ramp optics, compared to RHIC Run 13 and earlier runs, in relation with electron-lens beam-beam compensation developments. The new optics induces different strengths in the depolarizing snake resonance sequence, from injection to top energy. As a consequence, polarization transport along the new ramp has been investigated, based on spin tracking simulations. Sample results are reported and discussed.

  7. A Model of RHIC Using the Unified Accelerator Libraries

    Energy Technology Data Exchange (ETDEWEB)

    Pilat, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trahern, C. G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Malitsky, N. [Cornell Univ., Ithaca, NY (United States)

    1998-01-01

    The Unified Accelerator Library (UAL) is an object oriented and modular software environment for accelerator physics which comprises an accelerator object model for the description of the machine (SMF, for Standard Machine Format), a collection of Physics Libraries, and a Perl inte,face that provides a homo­geneous shell for integrating and managing these components. Currently available physics libraries include TEAPOT++, a collection of C++ physics modules conceptually derived from TEAPOT, and DNZLIB, a differential algebra package for map generation. This software environment has been used to build a flat model of RHIC which retains the hierarchical lat­tice description while assigning specific characteristics to individual elements, such as measured field har­monics. A first application of the model and of the simulation capabilities of UAL has been the study of RHIC stability in the presence of siberian snakes and spin rotators. The building blocks of RHIC snakes and rotators are helical dipoles, unconventional devices that can not be modeled by traditional accelerator phys­ics codes and have been implemented in UAL as Taylor maps. Section 2 describes the RHIC data stores, Section 3 the RHIC SMF format and Section 4 the RHIC spe­cific Perl interface (RHIC Shell). Section 5 explains how the RHIC SMF and UAL have been used to study the RHIC dynamic behavior and presents detuning and dynamic aperture results. If the reader is not familiar with the motivation and characteristics of UAL, we include in the Appendix an useful overview paper. An example of a complete set of Perl Scripts for RHIC simulation can also be found in the Appendix.

  8. THE RHIC INJECTION SYSTEM.

    Energy Technology Data Exchange (ETDEWEB)

    FISCHER,W.; GLENN,J.W.; MACKAY,W.W.; PTITSIN,V.; ROBINSON,T.G.; TSOUPAS,N.

    1999-03-29

    The RHIC injection system has to transport beam from the AGS-to-RHIC transfer line onto the closed orbits of the RHIC Blue and Yellow rings. This task can be divided into three problems. First, the beam has to be injected into either ring. Second, once injected the beam needs to be transported around the ring for one turn. Third, the orbit must be closed and coherent beam oscillations around the closed orbit should be minimized. We describe our solutions for these problems and report on system tests conducted during the RHIC Sextant test performed in 1997. The system will be fully commissioned in 1999.

  9. Polarization response of RHIC electron lens lattices

    International Nuclear Information System (INIS)

    Ranjbar, V. H.; Méot, F.; Bai, M.; Abell, D. T.; Meiser, D.

    2016-01-01

    Depolarization response for a system of two orthogonal snakes at irrational tunes is studied in depth using lattice independent spin integration. Particularly, we consider the effect of overlapping spin resonances in this system, to understand the impact of phase, tune, relative location and threshold strengths of the spin resonances. Furthermore, these results are benchmarked and compared to two dimensional direct tracking results for the RHIC e-lens lattice and the standard lattice. We then consider the effect of longitudinal motion via chromatic scans using direct six dimensional lattice tracking.

  10. Polarization response of RHIC electron lens lattices

    Directory of Open Access Journals (Sweden)

    V. H. Ranjbar

    2016-10-01

    Full Text Available Depolarization response for a system of two orthogonal snakes at irrational tunes is studied in depth using lattice independent spin integration. In particular we consider the effect of overlapping spin resonances in this system, to understand the impact of phase, tune, relative location and threshold strengths of the spin resonances. These results are benchmarked and compared to two dimensional direct tracking results for the RHIC e-lens lattice and the standard lattice. Finally we consider the effect of longitudinal motion via chromatic scans using direct six dimensional lattice tracking.

  11. RHIC spin: The first polarized proton collider

    International Nuclear Information System (INIS)

    Roser, T.

    1994-01-01

    The very successful program of QCD and electroweak tests at the high energy hadron colliders have shown that the perturbative QCD has progressed towards becoming a ''precision'' theory. At the same time, it has been shown that with the help of Siberian Snakes it is feasible to accelerate polarized protons to high enough energies where the proven methods of collider physics can be used to probe the spin content of the proton but also where fundamental tests of the spin effects in the standard model are possible. With Siberian Snakes the Relativistic Heavy Ion Collider (RHIC) will be the first collider to allow for 250 GeV on 250 GeV polarized proton collisions

  12. Spin Physics at RHIC

    International Nuclear Information System (INIS)

    Bland, L.C.

    2003-01-01

    The physics goals that will be addressed by colliding polarized protons at the Relativistic Heavy Ion Collider (RHIC) are described. The RHIC spin program provides a new generation of experiments that will unfold the quark, anti-quark and gluon contributions to the proton's spin. In addition to these longer term goals, this paper describes what was learned from the first polarized proton collisions at √(s)=200 GeV. These collisions took place in a five-week run during the second year of RHIC operation

  13. BROOKHAVEN: RHIC installation

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    This summer, the first superconducting magnet was installed in 3.8 kilometre tunnel for Brookhaven's RHIC heavy ion collider (October, page 31). Manufactured by Northrop Grumman's Electronics and System Integration Division, the magnet is the first of RHIC's 373 dipoles. In addition to the dipoles, Northrop Grumman will also provide 432 RHIC quadrupoles. The first quadrupole was delivered on 8 April, a month before the first dipole arrived for onsite testing prior to installation. RHIC will need 1,700 superconducting magnets - dipoles, quadrupoles, sextupoles and correcting magnets, 1,200 of which will be built by industry and the rest built at Brookhaven. The 300 sextupoles are being supplied by Everson Electric

  14. RHIC SPIN PROGRAM: MACHINE ASPECTS AND RECENT PROGRESS

    International Nuclear Information System (INIS)

    ROSER, T.

    1999-01-01

    High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. However, the acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian Snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian Snakes and polarimeters are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible

  15. Brookhaven: RHIC magnets

    International Nuclear Information System (INIS)

    Heppelman, Steve

    1990-01-01

    Last year, Brookhaven's proposal for a Relativistic Heavy Ion Collider - RHIC - was scrutinized by the US Department of Energy and deemed to be ready for construction funding. The hope is that the money will be voted soon so that construction can get underway at the start of the new US financial year in October. The 3.8 kilometre RHIC tunnel was completed ten years ago for the doomed Isabelle/CBA proton collider project

  16. Brookhaven: Ready for RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Ludlam, Tom

    1990-04-15

    With its RHIC - Relativistic Heavy Ion Collider - project now part of the budget proposed by US President Bush for fiscal year 1991, Brookhaven is about to start construction of a unique kind of high energy collider. At a time when accelerators handling particles - electrons, protons and their antimatter counterparts - are boosting beam energies for microscopes to probe evershorter distances, RHIC is envisioned as a great pressure-cooker for strongly interacting matter.

  17. Brookhaven: Ready for RHIC

    International Nuclear Information System (INIS)

    Ludlam, Tom

    1990-01-01

    With its RHIC - Relativistic Heavy Ion Collider - project now part of the budget proposed by US President Bush for fiscal year 1991, Brookhaven is about to start construction of a unique kind of high energy collider. At a time when accelerators handling particles - electrons, protons and their antimatter counterparts - are boosting beam energies for microscopes to probe evershorter distances, RHIC is envisioned as a great pressure-cooker for strongly interacting matter

  18. ELECTRON COOLING FOR RHIC

    International Nuclear Information System (INIS)

    Ben-Zvi, I.

    2001-01-01

    The Accelerator Collider Department (CAD) at Brookhaven National Laboratory is operating the Relativistic Heavy Ion Collider (RHIC), which includes the dual-ring, 3.834 km circumference superconducting collider and the venerable AGS as the last part of the RHIC injection chain. CAD is planning on a luminosity upgrade of the machine under the designation RHIC II. One important component of the RHIC II upgrade is electron cooling of RHIC gold ion beams. For this purpose, BNL and the Budker Institute of Nuclear Physics in Novosibirsk entered into a collaboration aimed initially at the development of the electron cooling conceptual design, resolution of technical issues, and finally extend the collaboration towards the construction and commissioning of the cooler. Many of the results presented in this paper are derived from the Electron Cooling for RHIC Design Report [1], produced by the, BINP team within the framework of this collaboration. BNL is also collaborating with Fermi National Laboratory, Thomas Jefferson National Accelerator Facility and the University of Indiana on various aspects of electron cooling

  19. ELECTRON COOLING FOR RHIC.

    Energy Technology Data Exchange (ETDEWEB)

    BEN-ZVI,I.

    2001-05-13

    The Accelerator Collider Department (CAD) at Brookhaven National Laboratory is operating the Relativistic Heavy Ion Collider (RHIC), which includes the dual-ring, 3.834 km circumference superconducting collider and the venerable AGS as the last part of the RHIC injection chain. CAD is planning on a luminosity upgrade of the machine under the designation RHIC II. One important component of the RHIC II upgrade is electron cooling of RHIC gold ion beams. For this purpose, BNL and the Budker Institute of Nuclear Physics in Novosibirsk entered into a collaboration aimed initially at the development of the electron cooling conceptual design, resolution of technical issues, and finally extend the collaboration towards the construction and commissioning of the cooler. Many of the results presented in this paper are derived from the Electron Cooling for RHIC Design Report [1], produced by the, BINP team within the framework of this collaboration. BNL is also collaborating with Fermi National Laboratory, Thomas Jefferson National Accelerator Facility and the University of Indiana on various aspects of electron cooling.

  20. RHIC Data Correlation Methodology

    International Nuclear Information System (INIS)

    Michnoff, R.; D'Ottavio, T.; Hoff, L.; MacKay, W.; Satogata, T.

    1999-01-01

    A requirement for RHIC data plotting software and physics analysis is the correlation of data from all accelerator data gathering systems. Data correlation provides the capability for a user to request a plot of multiple data channels vs. time, and to make meaningful time-correlated data comparisons. The task of data correlation for RHIC requires careful consideration because data acquisition triggers are generated from various asynchronous sources including events from the RHIC Event Link, events from the two Beam Sync Links, and other unrelated clocks. In order to correlate data from asynchronous acquisition systems a common time reference is required. The RHIC data correlation methodology will allow all RHIC data to be converted to a common wall clock time, while still preserving native acquisition trigger information. A data correlation task force team, composed of the authors of this paper, has been formed to develop data correlation design details and provide guidelines for software developers. The overall data correlation methodology will be presented in this paper

  1. Quench observation using quench antennas on RHIC IR quadrupole magnets

    International Nuclear Information System (INIS)

    Ogitsu, T.; Terashima, A.; Tsuchiya, K.; Ganetis, G.; Muratore, J.; Wanderer, P.

    1995-01-01

    Quench observation using quench antennas is now being performed routinely on RHIC dipole and quadrupole magnets. Recently, a quench antenna was used on a RHIC IR magnet which is heavily instrumented with voltage taps. It was confirmed that the signals detected in the antenna coils do not contradict the voltage tap signals. The antenna also detects a sign of mechanical disturbance which could be related to a training quench. This paper summarizes signals detected in the antenna and discusses possible causes of these signals

  2. Quench observation using quench antennas on RHIC IR quadrupole magnets

    International Nuclear Information System (INIS)

    Ogitsu, T.; Terashima, A.; Tsuchiya, K.; Ganetis, G.; Muratore, J.; Wanderer, P.

    1996-01-01

    Quench observation using quench antennas is now being performed routinely on RHIC dipole and quadrupole magnets. Recently, a quench antenna was used on a RHIC IR magnet which is heavily instrumented with voltage taps. It was confirmed that the signals detected in the antenna coils do not contradict the voltage tap signals. The antenna also detects a sign of mechanical disturbance which could be related to a training quench. This paper summarizes signals detected in the antenna and discusses possible causes of these signals

  3. RHIC FY15 pp Run RHIC and AGS polarization analysis

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Adams, P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-02-20

    The polarization information is important for the spin physics program in Relativistic Heavy Ion Collider (RHIC). There are discrepancies between AGS and RHIC polarization measurements. First, the face value of AGS polarization is higher than RHIC ones in general. Second, the measured polarization profile (described by the profile ratio R) is stronger in AGS than in RHIC. This note analyzes the polarization data from FY15 pp run period. The results show that the differences between AGS and RHIC polarization measurements are reasonable, but the R value difference is puzzling. The difference between blue and yellow ring is worth of spin simulation to explain.

  4. RHIC STATUS AND PLANS.

    Energy Technology Data Exchange (ETDEWEB)

    PILAT,R.

    2002-06-02

    RHIC ended successfully its second year of operation in January 2002 after a six month run with gold ions and two months of polarized proton collisions. I will review the machine performance and accomplishments, that include reaching design energy (100 GeV/u) and design luminosity during the gold run, and the first high energy (100 GeV) polarized proton collisions. I will also discuss the machine development strategy and the main performance milestones. The goals and plans for the shutdown and the nest run, scheduled to start in November 2002 have been the focus of a RHIC Retreat in March 2002. I will summarize findings and plans for the upcoming run and outline a vision for the nest few years of RHIC operation and upgrades.

  5. RHIC prefire protection masks

    International Nuclear Information System (INIS)

    Drees, A.; Biscardi, C.; Curcio, T.; Gassner, D.; DeSanto, L.; Fu, W.; Liaw, C. J.; Montag, C.; Thieberger, P.; Yip, K.

    2015-01-01

    The protection of the RHIC experimental detectors from damage due to beam hitting close upstream elements in cases of abort kicker prefires requires some dedicated precautionary measures with two general options: to bring the beam close to a limiting aperture (i.e. the beam pipe wall), as far upstream of the detector components as possible or, alternatively, to bring a limiting aperture close to the circulating beam. Spontaneous and random prefires of abort kicker modules (Pulse Forming Network, PFN) have a history as long as RHIC is being operated. The abort system consist of 5 kickers in per ring, each of them equipped with its own dedicated PFN.

  6. Proceedings of RIKEN BNL Research Center workwhop on RHIC spin

    Energy Technology Data Exchange (ETDEWEB)

    SOFFER,J.

    1999-10-06

    This RHIC Spin Workshop is the 1999 annual meeting of the RHIC Spin Collaboration, and the second to be hosted at Brookhaven and sponsored by the RIKEN BNL Research Center. The previous meetings were at Brookhaven (1998), Marseille (1996), MIT in 1995, Argonne 1994, Tucson in 1991, and the Polarized Collider Workshop at Penn State in 1990. As noted last year, the Center provides a home for combined work on spin by theorists, experimenters, and accelerator physicists. This proceedings, as last year, is a compilation of 1 page summaries and 5 selected transparencies for each speaker. It is designed to be available soon after the workshop is completed. Speakers are welcome to include web or other references for additional material. The RHIC spin program and RHIC are rapidly becoming reality. RHIC has completed its first commissioning run, as described here by Steve Peggs. The first Siberian Snake for spin has been completed and is being installed in RHIC. A new polarized source from KEK and Triumf with over 1 milliampere of polarized H{sup minus} is being installed, described by Anatoli Zelenski. They have had a successful test of a new polarimeter for RHIC, described by Kazu Kurita and Haixin Huang. Spin commissioning is expected next spring (2000), and the first physics run for spin is anticipated for spring 2001. The purpose of the workshop is to get everyone together about once per year and discuss goals of the spin program, progress, problems, and new ideas. They also have many separate regular forums on spin. There are spin discussion sessions every Tuesday, now organized by Naohito Saito and Werner Vogelsang. The spin discussion schedule and copies of presentations are posted on http://riksg01.rhic.bnl.gov/rsc. Speakers and other spinners are encouraged to come to BNL and to lead a discussion on your favorite idea. They also have regular polarimeter and snake meetings on alternate Thursdays, led by Bill McGahern, the lead engineer for the accelerator spin

  7. Proceedings of RIKEN BNL Research Center workshop on RHIC spin

    International Nuclear Information System (INIS)

    Soffer, J.

    1999-01-01

    This RHIC Spin Workshop is the 1999 annual meeting of the RHIC Spin Collaboration, and the second to be hosted at Brookhaven and sponsored by the RIKEN BNL Research Center. The previous meetings were at Brookhaven (1998), Marseille (1996), MIT in 1995, Argonne 1994, Tucson in 1991, and the Polarized Collider Workshop at Penn State in 1990. As noted last year, the Center provides a home for combined work on spin by theorists, experimenters, and accelerator physicists. This proceedings, as last year, is a compilation of 1 page summaries and 5 selected transparencies for each speaker. It is designed to be available soon after the workshop is completed. Speakers are welcome to include web or other references for additional material. The RHIC spin program and RHIC are rapidly becoming reality. RHIC has completed its first commissioning run, as described here by Steve Peggs. The first Siberian Snake for spin has been completed and is being installed in RHIC. A new polarized source from KEK and Triumf with over 1 milliampere of polarized H minus is being installed, described by Anatoli Zelenski. They have had a successful test of a new polarimeter for RHIC, described by Kazu Kurita and Haixin Huang. Spin commissioning is expected next spring (2000), and the first physics run for spin is anticipated for spring 2001. The purpose of the workshop is to get everyone together about once per year and discuss goals of the spin program, progress, problems, and new ideas. They also have many separate regular forums on spin. There are spin discussion sessions every Tuesday, now organized by Naohito Saito and Werner Vogelsang. The spin discussion schedule and copies of presentations are posted on http://riksg01.rhic.bnl.gov/rsc. Speakers and other spinners are encouraged to come to BNL and to lead a discussion on your favorite idea. They also have regular polarimeter and snake meetings on alternate Thursdays, led by Bill McGahern, the lead engineer for the accelerator spin effort

  8. Snake resonances

    International Nuclear Information System (INIS)

    Tepikian, S.

    1988-01-01

    Siberian Snakes provide a practical means of obtaining polarized proton beams in large accelerators. The effect of snakes can be understood by studying the dynamics of spin precession in an accelerator with snakes and a single spin resonance. This leads to a new class of energy independent spin depolarizing resonances, called snake resonances. In designing a large accelerator with snakes to preserve the spin polarization, there is an added constraint on the choice of the vertical betatron tune due to the snake resonances. 11 refs., 4 figs

  9. THE RHIC SEQUENCER

    International Nuclear Information System (INIS)

    VAN ZEIJTS, J.; DOTTAVIO, T.; FRAK, B.; MICHNOFF, R.

    2001-01-01

    The Relativistic Heavy Ion Collider (RHIC) has a high level asynchronous time-line driven by a controlling program called the ''Sequencer''. Most high-level magnet and beam related issues are orchestrated by this system. The system also plays an important task in coordinated data acquisition and saving. We present the program, operator interface, operational impact and experience

  10. RHIC injection kicker impedance

    International Nuclear Information System (INIS)

    Mane, V.; Peggs, S.; Trbojevic, D.; Zhang, W.

    1995-01-01

    The longitudinal impedance of the RHIC injection kicker is measured using the wire method up to a frequency of 3 GHz. The mismatch between the 50 ohm cable and the wire and pipe system is calibrated using the TRL calibration algorithm. Various methods of reducing the impedance, such as coated ceramic pipe and copper strips are investigated

  11. PHOBOS at RHIC 2000

    International Nuclear Information System (INIS)

    Garcia, E.; Baum, R.; Bindel, R.; Mignerey, A.; Shea, J.; Back, B.B.; Betts, R.R.; George, N.; Wuosmaa, A.H.; Baker, M.D.; Barton, D.S.; Carroll, A.; Ceglia, M.; Gushue, S.; Heintzelman, G.A.; Kraner, H.; Olszewski, A.; Pak, R.; Remsberg, L.P.; Scaduto, J.; Sinacore, J.; Steinberg, P.; Sukhanov, A.; Bogucki, W.; Budzanowski, A.; Coghen, T.; Dabrowski, B.; Despet, M.; Galuszka, K.; Godlewski, J.; Halik, J.; Holynski, R.; Kita, W.; Kotula, J.; Lemler, M.; Ligocki, J.; Michalowski, J.; Sawicki, P.; Straczek, A.; Stodulski, M.; Strek, M.; Stopa, Z.; Trzupek, A.; Wosiek, B.; Wozniak, K.; Zychowski, P.; Bialas, A.; Czyz, W.; Zalewski, K.; Basilev, S.; Bates, B.D.; Busza, W.; Decowski, M.P.; Fita, P.; Fitch, J.; Friedl, M.; Gomes, C.; Griesmayer, E.; Gulbrandsen, K.; Haridas, P.; Henderson, C.; Kane, J.; Katzy, J.; Kulinich, P.; Law, C.; Mulmenstadt, J.; Neal, M.; Patel, M.; Pernegger, H.; Plesko, M.; Reed, C.; Roland, C.; Roland, G.; Ross, D.; Rosenberg, L.; Ryan, J.; Sarin, P.; Steadman, S.G.; Stephans, G.S.F.; Surowiecka, K.; Vale, C.M.; Van Nieuwenhuizen, G.J.; Verdier, R.; Wadsworth, B.; Wyslouch, B.; Chang, Y.H.; Chen, A.E.; Lin, W.T.; Tang, J.L.; Conner, C.; Ganz, R.; Halliwell, C.; Hollis, R.; Holzman, B.; Kucewicz, W.; McLeod, D.; Nouicer, R.; Reuter, M.; Hayes, A.; Johnson, E.; Manly, S.; Park, I.C.; Skulski, W.; Teng, R.; Wolfs, F.L.H.; Sanzgiri, A.

    2001-01-01

    The relativistic heavy ion collider (RHIC) at Brookhaven national laboratory delivered in June 2000 the first collisions between Au nuclei at the highest center-of-mass energies achieved in a controlled environment to date. PHOBOS is one of the four experiments installed during this phase of RHIC running. This paper will describe the PHOBOS experiment, and discuss the results of the first physics measurement, thc pseudo rapidity densities of primary charged particles near mid rapidity in central Au + Au collisions at two different energies, √ S NN = 56 and 130 GeV. The observed densities are higher than those previously observed in any collisions, and the rate of increase between the two energies is larger than that for nucleon-nucleon collisions at comparable beam energies. This talk will describe the PHOBOS experiment, discuss the first physics measurement, and conclude with the present status of the experiment, the physics analysis and the perspectives fi the future. (Author)

  12. QCD and RHIC

    International Nuclear Information System (INIS)

    Kharzeev, D.

    2004-01-01

    In this talk I discuss recent advances in Quantum Chromo-Dynamics, in particular the progress in understanding the collective dynamics of the theory. I emphasise the significance of the RHIC program for establishing the properties of hot and dense QCD matter and for understanding the dynamics of the theory at the high parton density, strong color field frontier. Hopes and expectations for the future are discussed as well

  13. The RHIC status update

    International Nuclear Information System (INIS)

    Ozaki, S.

    1995-01-01

    The construction of the Relativistic Heavy Ion Collider (RHIC) began in 1991, with the completion date originally scheduled for 1997. Significant reduction of the funding levels in FY 1993 and 1994, and the funding level cap for FY 1995 and later years caused a 19-month stretchout of the construction period to the second quarter of FY 1999, and an increase of the total estimated cost (TEC) to $475 M. The Project, therefore, is now at the halfway mark of the construction period with actual cost and schedule performance tracking close to the DOE-approved baseline. Construction funding through FY 1994 reached close to 60% of the TEC. Incidentally, if one adds the current value of preexisting facilities which will be incorporated into RHIC, such as the injection system (Tandem Van de Graaff - the Booster - the AGS), the esixting 3.8 km tunnel, the 24 kW helium refrigerator, etc., the total value of the RHIC facility, when completed, will reach one billion dollars, if not more. The accelerator lattice design was finalized in 1992 after an intensive study was made to optimize the collider design for performance, operational flexibility, and value engineering. The civil construciton, including the collider enclosure, magnet access ports to the ring tunnel, and six service buildings for accelerator power supplies and cryogenic control boxes was completed

  14. A precise technique for manufacturing correction coil

    International Nuclear Information System (INIS)

    Schieber, L.

    1992-01-01

    An automated method of manufacturing correction coils has been developed which provides a precise embodiment of the coil design. Numerically controlled machines have been developed to accurately position coil windings on the beam tube. Two types of machines have been built. One machine bonds the wire to a substrate which is wrapped around the beam tube after it is completed while the second machine bonds the wire directly to the beam tube. Both machines use the Multiwire reg-sign technique of bonding the wire to the substrate utilizing an ultrasonic stylus. These machines are being used to manufacture coils for both the SSC and RHIC

  15. Numerical spin tracking in a synchrotron computer code Spink: Examples (RHIC)

    International Nuclear Information System (INIS)

    Luccio, A.

    1995-01-01

    In the course of acceleration of polarized protons in a synchrotron, many depolarizing resonances are encountered. They are classified in two categories: Intrinsic resonances that depend on the lattice structure of the ring and arise from the coupling of betatron oscillations with horizontal magnetic fields, and imperfection resonances caused by orbit distortions due to field errors. In general, the spectrum of resonances vs spin tune Gγ(G = 1.7928, the proton gyromagnetic anomaly, and y the proton relativistic energy ratio) for a given lattice tune ν, or vs ν for a given Gγ, contains a multitude of lines with various amplitudes or resonance strengths. The depolarization due to the resonance lines can be studied by numerically tracking protons with spin in a model accelerator. Tracking will allow one to check the strength of resonances, to study the effects of devices like Siberian Snakes, to find safe lattice tune regions where to operate, and finally to study in detail the operation of special devices such as Spin Flippers. A few computer codes exist that calculate resonance strengths E k and perform tracking, for proton and electron machines. Most relevant to our work for the AGS and RHIC machines are the programs Depol and Snake. Depol, calculates the E k 's by Fourier analysis. The input to Depol is the output of a machine model code, such as Synch or Mad, containing all details of the lattice. Snake, does the tracking, starting from a synthetic machine, that contains a certain number of periods, of FODO cells, of Siberian snakes, etc. We believed the complexities of machines like the AGS or RHIC could not be adequately represented by Snake. Then, we decided to write a new code, Spink, that combines some of the features of Depol and Snake. I.E., Spink reads a Mad output like Depol and tracks as Snake does. The structure of the code and examples for RHIC are described in the following

  16. Fast Automated Decoupling at RHIC

    CERN Document Server

    Beebe-Wang, Joanne

    2005-01-01

    Coupling correction is essential for the operational performance of RHIC. The independence of the transverse degrees of freedom makes diagnostics and tune control easier, and it is advantageous to operate an accelerator close to the coupling resonance to minimize nearby nonlinear sidebands. An automated decoupling application has been developed at RHIC for coupling correction during routine operations. The application decouples RHIC globally by minimizing the tune separation through finding the optimal settings of two orthogonal skew quadrupole families. The program provides options of automatic, semi-automatic and manual decoupling operations. It accesses tune information from all RHIC tune measurement systems: the PLL (Phase Lock Loop), the high frequency Schottky system, and the tune meter. It also supplies tune and skew quadrupole scans, finding the minimum tune separation, display the real time results and interface with the RHIC control system. We summarize the capabilities of the decoupling application...

  17. Polarized proton collider at RHIC

    International Nuclear Information System (INIS)

    Alekseev, I.; Allgower, C.; Bai, M.; Batygin, Y.; Bozano, L.; Brown, K.; Bunce, G.; Cameron, P.; Courant, E.; Erin, S.; Escallier, J.; Fischer, W.; Gupta, R.; Hatanaka, K.; Huang, H.; Imai, K.; Ishihara, M.; Jain, A.; Lehrach, A.; Kanavets, V.; Katayama, T.; Kawaguchi, T.; Kelly, E.; Kurita, K.; Lee, S.Y.; Luccio, A.; MacKay, W.W.; Mahler, G.; Makdisi, Y.; Mariam, F.; McGahern, W.; Morgan, G.; Muratore, J.; Okamura, M.; Peggs, S.; Pilat, F.; Ptitsin, V.; Ratner, L.; Roser, T.; Saito, N.; Satoh, H.; Shatunov, Y.; Spinka, H.; Syphers, M.; Tepikian, S.; Tominaka, T.; Tsoupas, N.; Underwood, D.; Vasiliev, A.; Wanderer, P.; Willen, E.; Wu, H.; Yokosawa, A.; Zelenski, A.N.

    2003-01-01

    In addition to heavy ion collisions (RHIC Design Manual, Brookhaven National Laboratory), RHIC will also collide intense beams of polarized protons (I. Alekseev, et al., Design Manual Polarized Proton Collider at RHIC, Brookhaven National Laboratory, 1998, reaching transverse energies where the protons scatter as beams of polarized quarks and gluons. The study of high energy polarized protons beams has been a long term part of the program at BNL with the development of polarized beams in the Booster and AGS rings for fixed target experiments. We have extended this capability to the RHIC machine. In this paper we describe the design and methods for achieving collisions of both longitudinal and transverse polarized protons in RHIC at energies up to √s=500 GeV

  18. PHOBOS at RHIC 2000

    Energy Technology Data Exchange (ETDEWEB)

    Back, B. B [Argonne National Laboratory (United States)] (and others)

    2001-12-01

    The relativistic heavy ion collider (RHIC) at Brookhaven national laboratory delivered in June 2000 the first collisions between Au nuclei at the highest center-of-mass energies achieved in a controlled environment to date. PHOBOS is one of the four experiments installed during this phase of RHIC running. This paper will describe the PHOBOS experiment, and discuss the results of the first physics measurement, the pseudo rapidity densities of primary charged particles near mid rapidity in central Au+Au collisions at two different energies, S{sub N}N{sup .}5=56 and 130 GeV. The observed densities are higher than those previously observed in any collisions, and the rate of increase between the two energies is larger than that for nucleon-nucleon collisions at comparable beam energies. This talk will describe the PHOBOS experiment, discuss the first physics measurement, and conclude with the present status of the experiment, the physics analysis and the perspectives for the future. [Spanish] El elativistic heavy ion collider (RHIC) en Brookhaven national laboratory produjo por primera vez colisiones de nucleos de oro (Au) a las energias mas altas alcanzadas en un medio ambiente controlado. PHOBOS es uno de los cuatro experimentos presentes en DIC durante su fase inicial. Este articulo describe en detalle a PHOBOS y discute los primeros resultados publicados acerca de la fisica de DIC, esto es la densidad de particulas primarias a id rapidity en colisiones centrales de Au+Au a dos diferentes energias S{sub N}N{sup .}5 =56 y 130 GeV. Las densidades observadas son mas altas que en cualquier otra experimento anterior, las densidades obtenidas son tambien mas altas que las encontradas en colisiones proton-proton a energias comparables. Este articulo tambien discute el estado actual del experimento asi como los planes para el futuro.

  19. Ramp Management in RHIC

    International Nuclear Information System (INIS)

    Kewisch, J.; Van Zeijts, J.; Peggs, S.; Satogata, T.

    1999-01-01

    In RHIC, magnets and RF cavities are controlled by Wave Form Generators (WFGs), simple real time computers which generate the set points. The WFGs are programmed to change set points from one state to another in a synchrotronized way. Such transition is called a ''Ramp'' and consists of a sequence of ''stepping stones'' which contain the set point of every WFG controlled device at a point in time. An appropriate interpolation defines the set points between these stepping stones. This report describes the implementation of the ramp system. The user interface, tools to create and modify ramps, interaction with modeling tools and measurements and correction programs are discussed

  20. RHIC electron lenses upgrades

    Energy Technology Data Exchange (ETDEWEB)

    Gu, X. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Altinbas, Z. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Binello, S. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Costanzo, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Drees, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Gassner, D. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Hock, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Hock, K. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Harvey, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Luo, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mi, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mernick, K. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Michnoff, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Miller, T. A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Pikin, A. I. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Samms, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Shrey, T. C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Schoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Tan, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Than, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; White, S. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2015-05-03

    In the Relativistic Heavy Ion Collider (RHIC) 100 GeV polarized proton run in 2015, two electron lenses were used to partially compensate for the head-on beam-beam effect for the first time. Here, we describe the design of the current electron lens, detailing the hardware modifications made after the 2014 commissioning run with heavy ions. A new electron gun with 15-mm diameter cathode is characterized. The electron beam transverse profile was measured using a YAG screen and fitted with a Gaussian distribution. During operation, the overlap of the electron and proton beams was achieved using the electron backscattering detector in conjunction with an automated orbit control program.

  1. SUPERCONDUCTING HELICAL SNAKE MAGNETS: CONSTRUCTION AND MEASUREMENTS

    International Nuclear Information System (INIS)

    Mackay, W.W.; Anerella, M.; Courant, E.

    1999-01-01

    In order to collide polarized protons, the RHIC project will have two snakes in each ring and four rotators around each of two interaction regions. Two snakes on opposite sides of each ring can minimize depolarization during acceleration by keeping the spin tune at a half. Since the spin direction is normally along the vertical direction in a flat ring, spin rotators must be used around an interaction point to have longitudinal polarization in a collider experiment. Each snake or rotator will be composed of four helical dipoles to provide the required rotation of spin with minimal transverse orbit excursions in a compact length of 10m. The basic helical dipole is a superconducting magnet producing a transverse dipole field which is twisted about the magnet axis through 360 o in a length of 2.4 m. The design and construction of the magnets is described in this paper

  2. ELECTRON COOLING FOR RHIC

    International Nuclear Information System (INIS)

    BEN-ZVI, I.; AHRENS, L.; BRENNAN, M.; HARRISON, M.; KEWISCH, J.; MACKAY, W.; PEGGS, S.; ROSER, T.; SATOGATA, T.; TRBOJEVIC, D.; YAKIMENKO, V.

    2001-01-01

    We introduce plans for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This project has a number of new features as electron coolers go: It will cool 100 GeV/nucleon ions with 50 MeV electrons; it will be the first attempt to cool a collider at storage-energy; and it will be the first cooler to use a bunched beam and a linear accelerator as the electron source. The linac will be superconducting with energy recovery. The electron source will be based on a photocathode gun. The project is carried out by the Collider-Accelerator Department at BNL in collaboration with the Budker Institute of Nuclear Physics

  3. RHIC control system

    Energy Technology Data Exchange (ETDEWEB)

    Barton, D.S. E-mail: dsbarton@bnl.gov; Binello, S.; Buxton, W.; Clifford, T.; D' Ottavio, T.; Hartmann, H.; Hoff, L.T.; Katz, R.; Kennell, S.; Kerner, T.; Laster, J.; Lee, R.C.; Marusic, A.; Michnoff, R.; Morris, J.; Oerter, B.R.; Olsen, R.; Piacentino, J.; Skelly, J.F

    2003-03-01

    The RHIC control system architecture is hierarchical and consists of two physical layers with a fiber-optic network connection. The Front-End Level systems consist of VME chassis with processors running a real-time operating system and both VME I/O modules and remote bus interfaces. Accelerator device software interfaces are implemented as objects in C++. The network implementation uses high speed, switched Ethernet technology. Specialized hardware modules were built for waveform control of power supplies, multiplexed signal acquisition, and timing services. The Console Level systems are Unix workstations. A strong emphasis has been given to developing highly reusable, standard software tools for use in building physics and diagnostic application software.

  4. RHIC control system

    International Nuclear Information System (INIS)

    Barton, D.S.; Binello, S.; Buxton, W.; Clifford, T.; D'Ottavio, T.; Hartmann, H.; Hoff, L.T.; Katz, R.; Kennell, S.; Kerner, T.; Laster, J.; Lee, R.C.; Marusic, A.; Michnoff, R.; Morris, J.; Oerter, B.R.; Olsen, R.; Piacentino, J.; Skelly, J.F.

    2003-01-01

    The RHIC control system architecture is hierarchical and consists of two physical layers with a fiber-optic network connection. The Front-End Level systems consist of VME chassis with processors running a real-time operating system and both VME I/O modules and remote bus interfaces. Accelerator device software interfaces are implemented as objects in C++. The network implementation uses high speed, switched Ethernet technology. Specialized hardware modules were built for waveform control of power supplies, multiplexed signal acquisition, and timing services. The Console Level systems are Unix workstations. A strong emphasis has been given to developing highly reusable, standard software tools for use in building physics and diagnostic application software

  5. Quadrupole beam-based alignment in the RHIC interaction regions

    International Nuclear Information System (INIS)

    Ziegler, J.; Satogata, T.

    2011-01-01

    Continued beam-based alignment (BBA) efforts have provided significant benefit to both heavy ion and polarized proton operations at RHIC. Recent studies demonstrated previously unknown systematic beam position monitor (BPM) offset errors and produced accurate measurements of individual BPM offsets in the experiment interaction regions. Here we describe the algorithm used to collect and analyze data during the 2010 and early 2011 RHIC runs and the results of these measurements. BBA data has been collected over the past two runs for all three of the active experimental IRs at RHIC, updating results from the 2005 run which were taken with incorrectly installed offsets. The technique was successfully applied to expose a systematic misuse of the BPM survey offsets in the control system. This is likely to benefit polarized proton operations as polarization transmission through acceleration ramps depends on RMS orbit control in the arcs, but a quantitative understanding of its impact is still under active investigation. Data taking is ongoing as are refinements to the BBA technique aimed at reducing systematic errors and properly accounting for dispersive effects. Further development may focus on non-triplet BPMs such as those located near snakes, or arc quadrupoles that do not have individually shunted power supplies (a prerequisite for the current method) and as such, will require a modified procedure.

  6. Physics and experiments at RHIC

    International Nuclear Information System (INIS)

    Young, G.R.

    1995-01-01

    The Relativistic Heavy Ion Collider (RHIC), under construction at Brookhaven National Laboratory, will be the site of a series of experiments seeking to discover the quark-gluon plasma and elucidate its properties. Several observables should exhibit characteristic behaviors if a quark-gluon plasma is indeed created in the laboratory. Four experiments are now under construction for RHIC to measure certain of these observables over kinematic ranges where effects due to quark-gluon plasma formation should be manifest

  7. Snake bites

    Science.gov (United States)

    ... number if someone has been bitten by a snake. If possible, call ahead to the emergency room so that antivenom can be ready when the person arrives. Your local poison center can be reached directly by calling the ...

  8. Electron Cooling of RHIC

    CERN Document Server

    Ben-Zvi, Ilan; Barton, Donald; Beavis, Dana; Blaskiewicz, Michael; Bluem, Hans; Brennan, Joseph M; Bruhwiler, David L; Burger, Al; Burov, Alexey; Burrill, Andrew; Calaga, Rama; Cameron, Peter; Chang, Xiangyun; Cole, Michael; Connolly, Roger; Delayen, Jean R; Derbenev, Yaroslav S; Eidelman, Yury I; Favale, Anthony; Fedotov, Alexei V; Fischer, Wolfram; Funk, L W; Gassner, David M; Hahn, Harald; Harrison, Michael; Hershcovitch, Ady; Holmes, Douglas; Hseuh Hsiao Chaun; Johnson, Peter; Kayran, Dmitry; Kewisch, Jorg; Kneisel, Peter; Koop, Ivan; Lambiase, Robert; Litvinenko, Vladimir N; MacKay, William W; Mahler, George; Malitsky, Nikolay; McIntyre, Gary; Meng, Wuzheng; Merminga, Lia; Meshkov, Igor; Mirabella, Kerry; Montag, Christoph; Nagaitsev, Sergei; Nehring, Thomas; Nicoletti, Tony; Oerter, Brian; Parkhomchuk, Vasily; Parzen, George; Pate, David; Phillips, Larry; Preble, Joseph P; Rank, Jim; Rao, Triveni; Rathke, John; Roser, Thomas; Russo, Thomas; Scaduto, Joseph; Schultheiss, Tom; Sekutowicz, Jacek; Shatunov, Yuri; Sidorin, Anatoly O; Skrinsky, Aleksander Nikolayevich; Smirnov, Alexander V; Smith, Kevin T; Todd, Alan M M; Trbojevic, Dejan; Troubnikov, Grigory; Wang, Gang; Wei, Jie; Williams, Neville; Wu, Kuo-Chen; Yakimenko, Vitaly; Zaltsman, Alex; Zhao, Yongxiang; ain, Animesh K

    2005-01-01

    We report progress on the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon at storage energy using 54 MeV electrons. The electron source will be a superconducting RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum electron bunch frequency is 9.38 MHz, with bunch charge of 20 nC. The R&D program has the following components: The photoinjector and its photocathode, the superconducting linac cavity, start-to-end beam dynamics with magnetized electrons, electron cooling calculations including benchmarking experiments and development of a large superconducting solenoid. The photoinjector and linac cavity are being incorporated into an energy recovery linac aimed at demonstrating ampere class current at about 20 MeV. A Zeroth Order Design Report is in an advanced draft state, and can be found on the web at http://www.ags...

  9. Polarized protons at RHIC

    International Nuclear Information System (INIS)

    Tannenbaum, M.J.

    1990-12-01

    The Physics case is presented for the use of polarized protons at RHIC for one or two months each year. This would provide a facility with polarizations of approx-gt 50% high luminosity ∼2.0 x 10 32 cm -2 s -1 , the possibility of both longitudinal and transverse polarization at the interaction regions, and frequent polarization reversal for control of systematic errors. The annual integrated luminosity for such running (∼10 6 sec per year) would be ∫ Ldt = 2 x 10 38 cm -2 -- roughly 20 times the total luminosity integrated in ∼ 10 years of operation of the CERN Collider (∼10 inverse picobarns, 10 37 cm -2 ). This facility would be unique in the ability to perform parity-violating measurements and polarization test of QCD. Also, the existence of p-p collisions in a new energy range would permit the study of ''classical'' reactions like the total cross section and elastic scattering, etc., and serve as a complement to measurements from p-bar p colliders. 11 refs

  10. Spin physics at RHIC

    International Nuclear Information System (INIS)

    Tannenbaum, M.J.

    1996-01-01

    Operation of RHIC with two beams of highly polarized protons (70%, either longitudinal or transverse) at high luminosity L = 2 x 10 32 cm -2 sec -1 for two months/year will allow the STAR and PHENIX detectors to perform high statististics studies of polarization phenomena in the perturbative region of hard scattering where both QCD and ElectroWeak theory make detailed predictions for polarization effects. The collision c.m. energy, √s = 200 - 500 GeV, represents a new domain for the study of spin. Direct photon production will be used to measure the gluon polarization in the polarized proton. A new twist comes from W-boson production which is expected to be 100% parity violating and will thus allow measurements of flavor separated Quark and antiquark (u, bar u, d, bar d) polarization distributions. Searches for parity violation in strong interaction processes such as jet and leading particle production will be a sensitive way to look for new physics beyond the standard model, one possibility being quark substructure

  11. FAST AUTOMATED DECOUPLING AT RHIC

    International Nuclear Information System (INIS)

    BEEBE-WANG, J.J.

    2005-01-01

    Coupling correction is essential for the operational performance of RHIC. The independence of the transverse degrees of freedom makes diagnostics and tune control easier, and it is advantageous to operate an accelerator close to the coupling resonance to minimize nearby nonlinear sidebands. An automated coupling correction application iDQmini has been developed for RHIC routine operations. The application decouples RHIC globally by minimizing the tune separation through finding the optimal settings of two orthogonal skew quadrupole families. The program iDQmini provides options of automatic, semi-automatic and manual decoupling operations. It accesses tune information from all RHIC tune measurement systems: the PLL (phase lock loop), the high frequency Schottky system and the tune meter. It also supplies tune and skew quadrupole scans, finding the minimum tune separation, display the real time results and interface with the RHIC control system. We summarize the capabilities of the coupling correction application iDQmini, and discuss the operational protections incorporated in the program

  12. The RHIC injection fast kicker

    International Nuclear Information System (INIS)

    Forsyth, E.B.; Pappas, G.C.; Tuozzolo, J.E.; Zhang, W.

    1995-01-01

    The purpose of the injection kicker is to provide the ultimate deflection to the incoming beam from the Alternating Gradient Synchrotron (AGS) into the Relativistic Heavy Ion Collider (RHIC). The beam is kicked in the vertical direction to place it on the equilibrium orbit of RHIC. Each bunch in the AGS is transferred separately, and stacked box-car fashion in the appropriate RHIC rf bucket. In order to achieve the required deflection angle four magnets powered by four pulsers will be used for each ring of RHIC. When the bunches are stacked in RHIC the last few rf buckets are left unfilled in order to provide a gap in the beam to facilitate the ejection or beam abort process. This also means there is not a severe constraint on the fall-time of the injection kicker. One prototype pulser has been built and tested. Much of the development effort has gone into the magnet design. Although lumped ferrite magnets are simpler to build and require less power to reach full field, a transmission line magnet was developed because of the very fast rise-time requirement and the tolerances imposed on the field variation and ripple

  13. RESEARCH PLAN FOR SPIN PHYSICS AT RHIC.

    Energy Technology Data Exchange (ETDEWEB)

    AIDALA, C.; BUNCE, G.; ET AL.

    2005-02-01

    In this report we present the research plan for the RHIC spin program. The report covers (1) the science of the RHIC spin program in a world-wide context; (2) the collider performance requirements for the RHIC spin program; (3) the detector upgrades required, including timelines; (4) time evolution of the spin program.

  14. Ion optics of RHIC EBIS

    Energy Technology Data Exchange (ETDEWEB)

    Pikin, A.; Alessi, J.; Beebe, E.; Kponou, A.; Okamura, M.; Raparia, D.; Ritter, J.; Tan, Y.; Kuznetsov, G.

    2011-09-10

    RHIC EBIS has been commissioned to operate as a versatile ion source on RHIC injection facility supplying ion species from He to Au for Booster. Except for light gaseous elements RHIC EBIS employs ion injection from several external primary ion sources. With electrostatic optics fast switching from one ion species to another can be done on a pulse to pulse mode. The design of an ion optical structure and the results of simulations for different ion species are presented. In the choice of optical elements special attention was paid to spherical aberrations for high-current space charge dominated ion beams. The combination of a gridded lens and a magnet lens in LEBT provides flexibility of optical control for a wide range of ion species to satisfy acceptance parameters of RFQ. The results of ion transmission measurements are presented.

  15. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER, VOLUME 37, RHIC SPIN COLLABORATION MEETING VI (PART 2)

    International Nuclear Information System (INIS)

    Bland, L.; Saito, N.

    2001-01-01

    The second part of the sixth RHIC Spin Collaboration (RSC) meeting was held on November 15, 2001 at Brookhaven National Laboratory. Previous meetings have elaborated on the new generation of proton spin-structure studies (e.g. gluon polarization and flavor separation of q and bar q polarizations via real W ± production) enabled by studying polarized proton collisions at energies and momentum transfers where perturbative QCD models are expected to be applicable. The focus of this meeting was on many of the experimental issues that must be resolved to achieve these physics goals. This summary is written with the benefit of hindsight following the completion of the first-ever run of a polarized proton collider. This first run can be considered as a successfully completed milestone of the RHIC Spin Collaboration. Other milestones remain important. Long term machine items were identified in Waldo Mackay's talk, the most important being the completion of the spin rotator magnets that will be installed in 2002 to allow the flexible orientation of the proton beam polarization at the PHENM and STAR experiments. At the meeting Waldo discussed a stronger partial snake magnet for the AGS as a means of producing highly polarized proton beams to inject into RHIC. Developments subsequent to this meeting suggest that a superconducting helical dipole magnet may be feasible for the AGS, and is likely to be needed to achieve the 70% beam polarization in RHIC. Longer term items were also presented, including potential increases in luminosity by the addition of electron cooling to RHIC and the possibility of increasing the collision energy by ∼20% by replacement of the DX magnets. These items could be considered for a second generation of RHIC spin experiments. The other topics covered at the meeting were related to polarimetry and to the absolute calibration of the proton beam polarization in RHIC. These topics were divided into short- and long-term solutions to polarimetry issues

  16. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER, VOLUME 37, RHIC SPIN COLLABORATION MEETING VI (PART 2).

    Energy Technology Data Exchange (ETDEWEB)

    BLAND, L.; SAITO, N.

    2001-11-15

    The second part of the sixth RHIC Spin Collaboration (RSC) meeting was held on November 15, 2001 at Brookhaven National Laboratory. Previous meetings have elaborated on the new generation of proton spin-structure studies (e.g. gluon polarization and flavor separation of q and {bar q} polarizations via real W{sup {+-}} production) enabled by studying polarized proton collisions at energies and momentum transfers where perturbative QCD models are expected to be applicable. The focus of this meeting was on many of the experimental issues that must be resolved to achieve these physics goals. This summary is written with the benefit of hindsight following the completion of the first-ever run of a polarized proton collider. This first run can be considered as a successfully completed milestone of the RHIC Spin Collaboration. Other milestones remain important. Long term machine items were identified in Waldo Mackay's talk, the most important being the completion of the spin rotator magnets that will be installed in 2002 to allow the flexible orientation of the proton beam polarization at the PHENM and STAR experiments. At the meeting Waldo discussed a stronger partial snake magnet for the AGS as a means of producing highly polarized proton beams to inject into RHIC. Developments subsequent to this meeting suggest that a superconducting helical dipole magnet may be feasible for the AGS, and is likely to be needed to achieve the 70% beam polarization in RHIC. Longer term items were also presented, including potential increases in luminosity by the addition of electron cooling to RHIC and the possibility of increasing the collision energy by {approx}20% by replacement of the DX magnets. These items could be considered for a second generation of RHIC spin experiments. The other topics covered at the meeting were related to polarimetry and to the absolute calibration of the proton beam polarization in RHIC. These topics were divided into short- and long-term solutions to

  17. RHIC off-line computing

    International Nuclear Information System (INIS)

    Featherly, J.; Gibbard, B.; Gould, J.

    1993-01-01

    A report was prepared in Sept 1992, RHIC/DET Note 8, also known as ROCOCO, which estimated the various computing resources which will be required by the RHIC experimental program. A study has now been undertaken to review technical issues associated with supplying these resources. This study, organized by the HEP/NP Computing Group but including other appropriate participants, addresses questions of technologies, manpower, cost and schedule. The following document is an interim summary of this study both in terms of discussions which have occurred and initial conclusions reached

  18. Parity violation experiments at RHIC

    International Nuclear Information System (INIS)

    Tannenbaum, M.J.

    1993-01-01

    With longitudinally polarized protons at RHIC, even a 1 month dedicated run utilizing both approved major detectors could produce a significant search for new physics in hadron collisions via parity violation. Additionally, in the energy range of RHIC, large ''conventional'' parity violating effects are predicted due to the direct production of the weak bosons W ± and Z 0 . One can even envision measurements of the spin dependent sea-quark structure functions of nucleons using the single-spin parity violating asymmetry of W ± and Z 0

  19. Mutual mortality of great horned owl and southern black racer: a potential risk of raptors preying on snakes

    Science.gov (United States)

    Roger W. Perry; Raymond E. Brown; D. Craig Rudolph

    2001-01-01

    We encountered a dead southern black racer snake (Coluber constrictor priapus) coiled around a dead Great Horned Owl (Bubo virginianus). We suggest the owl was strangled by the snake before the snake did of wounds inflicted by the owl. There are previous reports of intense physical struggle between Great Horned Owls (and...

  20. High density matter at RHIC

    Indian Academy of Sciences (India)

    QCD predicts a phase transition between hadronic matter and a quark-gluon plasma at high energy density. The relativistic heavy ion collider (RHIC) at Brookhaven National Laboratory is a new facility dedicated to the experimental study of matter under extreme conditions. Already the first round of experimental results at ...

  1. SCHOTTKY MEASUREMENTS DURING RHIC 2000

    International Nuclear Information System (INIS)

    CAMERON, P.; CUPOLO, J.; DEGEN, C.; HAMMONS, L.; KESSELMAN, M.; LEE, R.; MEYER, A.; SIKORA, R.

    2001-01-01

    The 2GHz Schottky system was a powerful diagnostic during RHIC 2000 commissioning. A continuous monitor without beam excitation, it provided betatron tune, chromaticity, momentum spread relative emittance, and synchrotron tune. It was particularly useful during transition studies. In addition, a BPM was resonated at 230MHz for Schottky measurements

  2. A snail-eating snake recognizes prey handedness.

    Science.gov (United States)

    Danaisawadi, Patchara; Asami, Takahiro; Ota, Hidetoshi; Sutcharit, Chirasak; Panha, Somsak

    2016-04-05

    Specialized predator-prey interactions can be a driving force for their coevolution. Southeast Asian snail-eating snakes (Pareas) have more teeth on the right mandible and specialize in predation on the clockwise-coiled (dextral) majority in shelled snails by soft-body extraction. Snails have countered the snakes' dextral-predation by recurrent coil reversal, which generates diverse counterclockwise-coiled (sinistral) prey where Pareas snakes live. However, whether the snake predator in turn evolves any response to prey reversal is unknown. We show that Pareas carinatus living with abundant sinistrals avoids approaching or striking at a sinistral that is more difficult and costly to handle than a dextral. Whenever it strikes, however, the snake succeeds in predation by handling dextral and sinistral prey in reverse. In contrast, P. iwasakii with little access to sinistrals on small peripheral islands attempts and frequently misses capturing a given sinistral. Prey-handedness recognition should be advantageous for right-handed snail-eating snakes where frequently encountering sinistrals. Under dextral-predation by Pareas snakes, adaptive fixation of a prey population for a reversal gene instantaneously generates a sinistral species because interchiral mating is rarely possible. The novel warning, instead of sheltering, effect of sinistrality benefitting both predators and prey could further accelerate single-gene ecological speciation by left-right reversal.

  3. Physics with tagged forward protons at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Yip,K.

    2009-08-30

    The physics reach of the STAR detector at RHIC has been extended to include elastic and inelastic diffraction measurements with tagged forward protons. This program has started at RHIC in p+p collisions with a special optics run of {beta}* {approx} 21 m at STAR, at the center-of-mass energy {radical}s = 200 GeV during the last week of the RHIC 2009 run.

  4. Prospects for spin physics at RHIC

    International Nuclear Information System (INIS)

    Robinett, R.W.; Pennsylvania State Univ., University Park, PA

    1995-06-01

    The proposal to perform polarized proton-proton collisions at collider energies at RHIC is reviewed. After a brief reminder of the desirability of high energy spin physics measurements, we discuss the machine parameters and detector features which are taken to define a program of spin physics at RHIC. Some of the many physics processes which can provide information on polarized parton distributions and the spin-dependence of QCD and the electroweak model at RHIC energies are discussed

  5. RHIC Sextant Test -- Physics and performance

    International Nuclear Information System (INIS)

    Wei, J.; Fischer, W.; Ahrens, L.

    1997-01-01

    This paper presents beam physics and machine performance results of the Relativistic Heavy Ion Collider (RHIC) Sextant and AGS-to-RHIC (AtR) transfer line during the Sextant Test in early 1997. Techniques used to measure both machine properties (difference orbits, dispersion, and beamline optics) and beam parameters (energy, intensity, transverse and longitudinal emittances) are described. Good agreement was achieved between measured and design lattice optics. The gold ion beam quality was shown to approach RHIC design requirements

  6. Tau electron atoms at RHIC

    International Nuclear Information System (INIS)

    Weiss, M.S.

    1985-01-01

    An amusement ancillary to the proposed quark-gluon plasma production hypothesized from a relativistic heavy ion collider (RHIC is a sufficient quantity of tau electrons to potentially admit the study of its exotic atoms. In this paper the given wealth of nuclear phenomena is derived from muonic atoms assume a tau atom is more forthcoming of information due to the lower orbits entirely contained within the nucleus. It is the purpose of this brief note to discuss the production mechanism at a RHIC and to delineate some of the more obvious properties of the tau atom. As in the case of the mu, more exotic phenomena derived from resonance ''accidents'' with nuclear transitions takes place, but it would be presumptions to discuss them at this time. Given the complete containment in nuclear matter of the tau lepton in its innermost atomic orbits. An experiment performed with such an exotic species results in the measurement of its lifetime

  7. Workshop on the RHIC performance

    Energy Technology Data Exchange (ETDEWEB)

    Khiari, F.; Milutinovic, J.; Ratti, A.; Rhoades-Brown, M.J. (eds.)

    1988-07-01

    The most recent conceptual design manual for the Relativistic Heavy Ion Collider (RHIC) at Brookhaven was published in May 1986 (BNL 51932). The purpose of this workshop was to review the design specifications in this RHIC reference manual, and to discuss in detail possible improvements in machine performance by addressing four main areas. These areas are beam-beam interactions, stochastic cooling, rf and bunch instabilities. The contents of this proceedings are as follows. Following an overview of the workshop, in which the motivation and goals are discussed in detail, transcripts of the first day talks are given. Many of these transcripts are copies of the original transparencies presented at the meeting. The following four sections contain contributed papers, that resulted from discussions at the workshop within each of the four working groups. In addition, there is a group summary for each of the four working groups at the beginning of each section. Finally, a list of participants is given.

  8. Beam profile measurements on RHIC

    International Nuclear Information System (INIS)

    Connolly, R.; Michnoff, R.; Moore, T.; Shea, T.; Tepikian, S.

    2000-01-01

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Lab was commissioned during the summer of 1999. Transverse beam profiles on RHIC are measured with ionization profile monitors (IPMs). An IPM measures beam profiles by collecting the electrons liberated by residual gas ionization by the beam. The detector is placed in the gap of a dipole magnet to force the electrons to travel in straight lines from the beamline center to the collector. One IPM was tested and it measured the profiles of a single gold bunch containing 10 8 ions on consecutive turns. We show an example of one of these profiles giving transverse emittance. Also several profiles are combined into a mountain-range plot which shows betatron oscillations at injection

  9. Transverse energy production at RHIC

    International Nuclear Information System (INIS)

    Sahoo, Raghunath

    2006-01-01

    The quest for understanding of the possible formation and existence of the quark-gluon plasma (Qp), the deconfined phase of quarks and gluons, has been a major area of research in high energy nuclear physics. High energy nuclear collisions at the Relativistic Heavy Ion Collider (RHIC) has opened a new domain for the exploration of strongly interacting matter at very high energy density and temperature

  10. Monolithic readout circuits for RHIC

    International Nuclear Information System (INIS)

    O'Connor, P.; Harder, J.; Sippach, W.

    1991-10-01

    Several CMOS ASICs have been developed for a proposed RHIC experiment. This paper discusses why ASIC implementation was chosen for certain functions, circuit specifications and the design techniques used to meet them, and results of simulations and early prototypes. By working closely together from an early stage in the planning process, in-house ASIC designers and detector and data acquisition experimenters can achieve optimal use of this important technology

  11. Monolithic readout circuits for RHIC

    Energy Technology Data Exchange (ETDEWEB)

    O`Connor, P.; Harder, J. [Brookhaven National Laboratory, Upton, NY (United States)

    1991-12-31

    Several CMOS ASICs have been developed for a proposed RHIC experiment. This paper discusses why ASIC implementation was chosen for certain functions, circuit specifications and the design techniques used to meet them, and results of simulations and early prototypes. By working closely together from an early stage in the planning process, in-house ASIC designers and detector and data acquisition experimenters can achieve optimal use of this important technology.

  12. The STAR experiment at RHIC

    International Nuclear Information System (INIS)

    Marx, J.N.

    1994-01-01

    STAR (Solenoidal Tracker at RHIC) will be one of two large, sophisticated experiments ready to take data when the Relativistic Heavy Ion Collider (RHIC) comes on-line in 1999. The design of STAR, its construction and commissioning and the physics program using the detector are the responsibility of a collaboration of over 250 members from 30 institutions, world-wide. The overall approach of the STAR Collaboration to the physics challenge of studying collisions of highly relativistic nuclei is to focus on measurements of the properties of the many hadrons produced in the collisions. The STAR detector is optimized to detect and identify hadrons over a large solid angle so that individual events can be characterized, in detail, based on their hadronic content. The broad capabilities of the STAR detector will permit an examination of a wide variety of proposed signatures for the Quark Gluon Plasma (QGP), using the sample of events which, on an event-by-event basis, appear to come from collisions resulting in a large energy density over a nuclear volume. In order to achieve this goal, the STAR experiment is based on a solenoid geometry with tracking detectors using the time projection chamber approach and covering a large range of pseudo-rapidity so that individual tracks can be seen within the very high track density expected in central collisions at RHIC. STAR also uses particle identification by the dE/dx technique and by time-of-flight. Electromagnetic energy is detected in a large, solid-angle calorimeter. The construction of STAR, which will be located in the Wide Angle Hall at the 6 o'clock position at RHIC, formally began in early 1993

  13. Production of quarkonia at RHIC

    Czech Academy of Sciences Publication Activity Database

    Vértési, Robert

    2016-01-01

    Roč. 31, 28-29 (2016), č. článku 1645036. ISSN 0217-751X R&D Projects: GA ČR GA13-20841S Institutional support: RVO:61389005 Keywords : Brookhaven RHIC Coll * quark onium: heavy * quark onium: production * quark gluon: plasma Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.597, year: 2016

  14. DESIGN ISSUES FOR THE RHIC EBIS

    International Nuclear Information System (INIS)

    Beebe, E.; Alessi, J.; Kponou, A.; Pikin, A.; Prelec, K.; Kuznetzov, G.; Tiunov, M.

    2000-01-01

    Promising results are currently being obtained on the BNL Electron Beam Test Stand (EBTS), which is a prototype for the Relativistic Heavy Ion Collider (RHIC) EBIS. Based on the present-results, a proposal has been made regarding the general design of the RHIC EBIS. During the next year experiments will be made to investigate physics issues and beam properties important to the detailed design of the RHIC EBIS. Below we have outlined some of the physics issues to be explored experimentally, beam diagnostics that will be employed, and hardware modifications that are desired to go from the prototype stage to the RHIC EBIS

  15. Joining the RHIC Online and Offline Models

    CERN Document Server

    Malitsky, Nikolay; Fedotov, Alexei V; Kewisch, Jorg; Luccio, Alfredo U; Pilat, Fulvia Caterina; Ptitsyn, Vadim; Satogata, Todd; Talman, Richard M; Tepikian, Steven; Wei, Jie

    2005-01-01

    The paper presents an interface encompassing the RHIC online ramp model and the UAL offline simulation framework. The resulting consolidated facility aims to minimize the gap between design and operational data, and to facilitate analysis of RHIC performance and future upgrades in an operational context. The interface is based on the Accelerator Description Exchange Format (ADXF), and represents a snapshot of the RHIC online model which is in turn driven by machine setpoints. This approach is also considered as an intermediate step towards integrating the AGS and RHIC modeling environments to produce a unified online and offline AGS model for operations.

  16. Theoretical Status of the RHIC Program

    International Nuclear Information System (INIS)

    Jalilian-Marian, Jamal

    2006-01-01

    Since the beginning of its operation, the Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Lab has produced a wealth of exciting and interesting results. I give a brief overview of the theoretical aspects of the main results from the RHIC program

  17. Advantages of polarization experiments at RHIC

    International Nuclear Information System (INIS)

    Underwood, D.G.

    1991-01-01

    We point out various spin experiments that could be done if the polarized beam option is pursued at RHIC. The advantages of RHIC for investigating several current and future physics problems are discussed. In particular, the gluon spin dependent structure function of the nucleon could be measured cleanly and systematically. Relevant experience developed in conjunction with the Fermilab Polarized Beam program is also presented

  18. Results from STAR experiment at RHIC

    Indian Academy of Sciences (India)

    We present some of the important experimental results from nucleus–nucleus collision studies carried out by the STAR experiment at Relativistic Heavy Ion Collider (RHIC). The results suggests that central Au+Au collisions at RHIC has produced a dense and rapidly thermalizing matter with initial energy densities above the ...

  19. Elastic proton-proton scattering at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Yip, K.

    2011-09-03

    Here we describe elastic proton+proton (p+p) scattering measurements at RHIC in p+p collisions with a special optics run of {beta}* {approx} 21 m at STAR, at the center-of-mass energy {radical}s = 200 GeV during the last week of the RHIC 2009 run. We present preliminary results of single and double spin asymmetries.

  20. RHIC sextant test: Accelerator systems and performance

    Energy Technology Data Exchange (ETDEWEB)

    Pilat, F.; Trbojevic, D.; Ahrens, L. [and others

    1997-08-01

    One sextant of the RHIC Collider was commissioned in early 1997 with beam. We describe here the performance of the accelerator systems, instrumentation subsystems and application software. We also describe a ramping test without beam that took place after the commissioning with beam. Finally, we analyze the implications of accelerator systems performance and their impact on the planning for RHIC installation and commissioning.

  1. RHIC sextant test: Accelerator systems and performance

    International Nuclear Information System (INIS)

    Pilat, F.; Trbojevic, D.; Ahrens, L.

    1997-01-01

    One sextant of the RHIC Collider was commissioned in early 1997 with beam. We describe here the performance of the accelerator systems, instrumentation subsystems and application software. We also describe a ramping test without beam that took place after the commissioning with beam. Finally, we analyze the implications of accelerator systems performance and their impact on the planning for RHIC installation and commissioning

  2. The color class condensate RHIC and HERA

    CERN Document Server

    McLerran, L

    2002-01-01

    In this talk, I discuss a universal form of matter, the color glass condensate. It is this matter which composes the low x part of all hadronic wavefunctions. The experimental programs at RHIC and HERA, and future programs at LHC and RHIC may allow us to probe and study the properties of this matter. (8 refs).

  3. 4-twist helix snake to maintain polarization in multi-GeV proton rings

    Directory of Open Access Journals (Sweden)

    F. Antoulinakis

    2017-09-01

    Full Text Available Solenoid Siberian snakes have successfully maintained polarization in particle rings below 1 GeV, but never in multi-GeV rings, because the spin rotation by a solenoid is inversely proportional to the beam momentum. High energy rings, such as Brookhaven’s 255 GeV Relativistic Heavy Ion Collider (RHIC, use only odd multiples of pairs of transverse B-field Siberian snakes directly opposite each other. When it became impractical to use a pair of Siberian Snakes in Fermilab’s 120  GeV/c Main Injector, we searched for a new type of single Siberian snake that could overcome all depolarizing resonances in the 8.9–120  GeV/c range. We found that a snake made of one 4-twist helix and 2 dipoles could maintain the polarization. This snake design could solve the long-standing problem of significant polarization loss during acceleration of polarized protons from a few GeV to tens of GeV, such as in the AGS, before injecting them into multi-hundred GeV rings, such as RHIC.

  4. 4-twist helix snake to maintain polarization in multi-GeV proton rings

    Science.gov (United States)

    Antoulinakis, F.; Chen, Y.; Dutton, A.; Rossi De La Fuente, E.; Haupert, S.; Ljungman, E. A.; Myers, P. D.; Thompson, J. K.; Tai, A.; Aidala, C. A.; Courant, E. D.; Krisch, A. D.; Leonova, M. A.; Lorenzon, W.; Raymond, R. S.; Sivers, D. W.; Wong, V. K.; Yang, T.; Derbenev, Y. S.; Morozov, V. S.; Kondratenko, A. M.

    2017-09-01

    Solenoid Siberian snakes have successfully maintained polarization in particle rings below 1 GeV, but never in multi-GeV rings, because the spin rotation by a solenoid is inversely proportional to the beam momentum. High energy rings, such as Brookhaven's 255 GeV Relativistic Heavy Ion Collider (RHIC), use only odd multiples of pairs of transverse B-field Siberian snakes directly opposite each other. When it became impractical to use a pair of Siberian Snakes in Fermilab's 120 GeV /c Main Injector, we searched for a new type of single Siberian snake that could overcome all depolarizing resonances in the 8.9 - 120 GeV /c range. We found that a snake made of one 4-twist helix and 2 dipoles could maintain the polarization. This snake design could solve the long-standing problem of significant polarization loss during acceleration of polarized protons from a few GeV to tens of GeV, such as in the AGS, before injecting them into multi-hundred GeV rings, such as RHIC.

  5. 4-twist helix snake to maintain polarization in multi-GeV proton rings

    International Nuclear Information System (INIS)

    Antoulinakis, F.; Chen, Y.; Dutton, A.; Rossi De La Fuente, E.; Haupert, S.

    2017-01-01

    Solenoid Siberian snakes have successfully maintained polarization in particle rings below 1 GeV, but never in multi-GeV rings, because the spin rotation by a solenoid is inversely proportional to the beam momentum. High energy rings, such as Brookhaven’s 255 GeV Relativistic Heavy Ion Collider (RHIC), use only odd multiples of pairs of transverse B-field Siberian snakes directly opposite each other. When it became impractical to use a pair of Siberian Snakes in Fermilab’s 120 GeV/c Main Injector, we searched for a new type of single Siberian snake that could overcome all depolarizing resonances in the 8.9–120 GeV/c range. We found that a snake made of one 4-twist helix and 2 dipoles could maintain the polarization. Here, this snake design could solve the long-standing problem of significant polarization loss during acceleration of polarized protons from a few GeV to tens of GeV, such as in the AGS, before injecting them into multi-hundred GeV rings, such as RHIC.

  6. Monkey pulvinar neurons fire differentially to snake postures.

    Science.gov (United States)

    Le, Quan Van; Isbell, Lynne A; Matsumoto, Jumpei; Le, Van Quang; Hori, Etsuro; Tran, Anh Hai; Maior, Rafael S; Tomaz, Carlos; Ono, Taketoshi; Nishijo, Hisao

    2014-01-01

    There is growing evidence from both behavioral and neurophysiological approaches that primates are able to rapidly discriminate visually between snakes and innocuous stimuli. Recent behavioral evidence suggests that primates are also able to discriminate the level of threat posed by snakes, by responding more intensely to a snake model poised to strike than to snake models in coiled or sinusoidal postures (Etting and Isbell 2014). In the present study, we examine the potential for an underlying neurological basis for this ability. Previous research indicated that the pulvinar is highly sensitive to snake images. We thus recorded pulvinar neurons in Japanese macaques (Macaca fuscata) while they viewed photos of snakes in striking and non-striking postures in a delayed non-matching to sample (DNMS) task. Of 821 neurons recorded, 78 visually responsive neurons were tested with the all snake images. We found that pulvinar neurons in the medial and dorsolateral pulvinar responded more strongly to snakes in threat displays poised to strike than snakes in non-threat-displaying postures with no significant difference in response latencies. A multidimensional scaling analysis of the 78 visually responsive neurons indicated that threat-displaying and non-threat-displaying snakes were separated into two different clusters in the first epoch of 50 ms after stimulus onset, suggesting bottom-up visual information processing. These results indicate that pulvinar neurons in primates discriminate between poised to strike from those in non-threat-displaying postures. This neuronal ability likely facilitates behavioral discrimination and has clear adaptive value. Our results are thus consistent with the Snake Detection Theory, which posits that snakes were instrumental in the evolution of primate visual systems.

  7. COMMISSIONING SPIN ROTATORS IN RHIC

    International Nuclear Information System (INIS)

    MACKAY, W.W.; AHRENS, L.; BAI, M.; COURANT, E.D.; FISCHER, W.; HUANG, H.; LUCCIO, A.; MONTAG, C.; PILAT, F.; PTITSYN, V.; ROSER, T.; SATOGATA, T.; TRBOJEVIC, D.; VANZIEJTS, J.

    2003-01-01

    During the summer of 2002, eight superconducting helical spin rotators were installed into RHIC in order to control the polarization directions independently at the STAR and PHENIX experiments. Without the rotators, the orientation of polarization at the interaction points would only be vertical. With four rotators around each of the two experiments, we can rotate either or both beams from vertical into the horizontal plane through the interaction region and then back to vertical on the other side. This allows independent control for each beam with vertical, longitudinal, or radial polarization at the experiment. In this paper, we present results from the first run using the new spin rotators at PHENIX

  8. INTENSITY DEPENDENT EFFECTS IN RHIC

    International Nuclear Information System (INIS)

    WEI, J.

    1999-01-01

    The Relativistic Heavy Ion Collider (RHIC) is currently under commissioning after a seven-year construction cycle. Unlike conventional hadron colliders, this machine accelerates, stores, and collides heavy ion beams of various combinations of species. The dominant intensity dependent effects are intra-beam scattering at both injection and storage, and complications caused by crossing transition at a slow ramp rate. In this paper, the authors present theoretical formalisms that have been used for the study, and discuss mechanisms, impacts, and compensation methods including beam cooling and transition jump schemes. Effects of space charge, beam-beam, and ring impedances are also summarized

  9. The PHENIX experiment at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Tonse, S.R.; Thomas, J.H.

    1993-12-15

    Later this decade the Relativistic Heavy Ion Collider (RHIC) will be built at Brookhaven National Laboratory. Its goal will be to accelerate and collide Au beams at 100 GeV/c in an attempt to create a Quark Gluon Plasma (QGP). The PHENIX detector aims to detect the QGP through its leptonic and hadronic signatures. We describe here its physics capabilities and the details of the apparatus designed to pick out rare leptonic signatures from among hadronic multiplicities of up to 1500 particles per unit of rapidity.

  10. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP, VOLUME 65, RHIC SPIN COLLABORATION MEETINGS XXVII, XXVIII, and XXX

    International Nuclear Information System (INIS)

    OGAWA, A.

    2004-01-01

    operational. A 10 teraflops QCDOC computer iis under construction and expected to be completed this year. This volume, 65, consists of papers from three RHIC Spin Collaboration meetings. Meeting XXVII held July 22, 2004 had 7 presentations: RHIC pp FY05 Run Preparation; AGS Cold Snake Status; PHENIX Spin Run-5 Beam Use Proposal; STAR FY05 Beam Use Request and Beyond; Update on the H-Jet; H-Jet Problems and Plans; and RHIC Polarimetry. Meeting XXVIII held September 2, 2004 had 6 presentations: Magnetic Measurement Results in the AGS Cold Snake HSD601 (a.k.a. DSM101); AGS Cold Snake Update; Preliminary Results and Interpretation of A N Measurement with pp2pp; Update on the H-Jet; Update on RHIC pC CNI Analysis; and A Few Polarimeter Studies. Meeting XXX held December 6, 2004 had 5 presentations: Polarized Proton Operations in AGS and RHIC; RHIC Status and Plan; Status and Commissioning Plans of AGS Cold Snake; Radial Polarization from RHIC CNI; and Relative Luminosity Measurement at PHENIX

  11. Dictionary Snakes

    DEFF Research Database (Denmark)

    Dahl, Anders Bjorholm; Dahl, Vedrana Andersen

    2014-01-01

    for image segmentation that operates without training data. Our method is based on a probabilistic dictionary of image patches coupled with a deformable model inspired by snakes and active contours without edges. We separate the image into two classes based on the information provided by the evolving curve......, which moves according to the probabilistic information obtained from the dictionary. Initially, the image patches are assigned to the nearest dictionary element, where the image is sampled at each pixel such that patches overlap. The curve divides the image into an inside and an outside region allowing...... us to estimate the pixel-wise probability of the dictionary elements. In each iteration we evolve the curve and update the probabilities, which merges similar texture patterns and pulls dissimilar patterns apart. We experimentally evaluate our approach, and show how textured objects are precisely...

  12. RHIC beam position monitor assemblies

    International Nuclear Information System (INIS)

    Cameron, P.R.; Grau, M.C.; Ryan, W.A.; Shea, T.J.; Sikora, R.E.

    1993-01-01

    Design calculations, design details, and fabrication techniques for the RHIC BPM Assemblies are discussed. The 69 mm aperture single plane detectors are 23 cm long short-circuited 50 ohm strip transmission lines subtending 80 degrees. They are mounted on the sextupole end of the Corrector-Quadrupole-Sextupole package and operate at liquid helium temperature. The 69 cm aperture was selected to be the same as that of the beampipe in the CQS package, the 23 cm length is a compromise between mechanical stability and electrical sensitivity to the long low-intensity proton and heavy ion bunches to be found in RHIC during commissioning, and the 80 degree subtended angle maximizes linear aperture. The striplines are aligned after brazing to maintain electrical-to-mechanical centers within 0.1 mm radius, eliminating the need for individual calibration. Because the cryogenic feedthrus isolate the UHV beam vacuum only from the HV insulating vacuum, and do not see liquid helium, a replaceable mini-ConFlat design was chosen to simplify fabrication, calibration, and maintenance

  13. RHIC Beam Position Monitor Assemblies

    International Nuclear Information System (INIS)

    Cameron, P.R.; Grau, M.C.; Ryan, W.A.; Shea, T.J.; Sikora, R.E.

    1993-01-01

    Design calculations, design details, and fabrication techniques for the RHIC BPM Assemblies are discussed. The 69 mm aperture single plane detectors are 23 cm long short-circuited 50 ohm strip transmission lines subtending 80 degrees. They are mounted on the sextupole end of the Corrector-Quadrupole-Sextupole package and operate at liquid helium temperature. The 69 cm aperture was selected to be the same as that of the beampipe in the CQS package, dc 23 cm length is a compromise between mechanical stability and electrical sensitivity to the long low-intensity proton and heavy ion bunches to be found in RHIC during commissioning, and the 80 degree subtended angle maximizes linear aperture. The striplines are aligned after brazing to maintain electrical-to-mechanical centers within 0.1 mm radius, eliminating the need for individual calibration. Because the cryogenic feedthrus isolate the UHV beam vacuum only from the HV insulating vacuum, and do not see liquid helium, a replaceable mini-ConFlat design was chosen to simplify fabrication, calibration, and maintenance

  14. Reproductive Disorders in Snakes.

    Science.gov (United States)

    Di Girolamo, Nicola; Selleri, Paolo

    2017-05-01

    Reproduction of snakes is one of the challenging aspects of herpetology medicine. Due to the complexity of reproduction, several disorders may present before, during, or after this process. This article describes the physical examination, and radiographic, ultrasonographic, and endoscopic findings associated with reproductive disorders in snakes. Surgical techniques used to resolve reproductive disorders in snakes are described. Finally, common reproductive disorders in snakes are individually discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. The complexity of snake

    NARCIS (Netherlands)

    De Biasi, M.; Ophelders, T.

    2016-01-01

    Snake and Nibbler are two well-known video games in which a snake slithers through a maze and grows as it collects food. During this process, the snake must avoid any collision with its tail. Various goals can be associated with these video games, such as avoiding the tail as long as possible, or

  16. Even order snake resonances

    International Nuclear Information System (INIS)

    Lee, S.Y.

    1993-01-01

    We found that the perturbed spin tune due to the imperfection resonance plays an important role in beam depolarization at snake resonances. We also found that even order snake resonances exist in the overlapping intrinsic and imperfection resonances. Due to the perturbed spin tune shift of imperfection resonances, each snake resonance splits into two

  17. HIGH PT MEASUREMENT AT RHIC

    International Nuclear Information System (INIS)

    MIODUSZEWSKI, S.

    2003-01-01

    We present recent high transverse momentum measurements in Au+Au and p+p collisions at the Relativistic Heavy Ion Collider (RHIC). We define and show the nuclear modification factor for neutral pions and charged hadrons and discuss the particle species dependence. By means of the nuclear modification factor, we observe a suppression factor at high p T of 5-6 for neutral pions and 3-4 for charged hadrons in central Au+Au collisions relative to the binary-scaled yields in p+p (or peripheral) collisions. Finally we present strong evidence for the observation of jets in Au+Au collisions and the disappearance of the away-side jet in central Au+Au collisions

  18. RHIC heavy ion operations performance

    CERN Document Server

    Satogata, T; Ferrone, R; Pilat, F

    2006-01-01

    The Relativistic Heavy Ion Collider (RHIC) completed its fifth year of operation in 2005, colliding copper ion beams with ps=200 GeV/u and 62.4 GeV/u[1]. Previous heavy ion runs have collided gold ions at ps=130 GeV/u, 200 GeV/u, and 62.4 GeV/u[2], and deuterons and gold ions at ps=200 GeV/u[3]. This paper discusses operational performance statistics of this facility, including Cu- Cu delivered luminosity, availability, calendar time spent in physics stores, and time between physics stores. We summarize the major factors affecting operations efficiency, and characterize machine activities between physics stores.

  19. ABORT GAP CLEANING IN RHIC

    International Nuclear Information System (INIS)

    DREES, A.; AHRENS, L.; III FLILLER, R.; GASSNER, D.; MCINTYRE, G.T.; MICHNOFF, R.; TRBOJEVIC, D.

    2002-01-01

    During the RHIC Au-run in 2001 the 200 MHz storage cavity system was used for the first time. The rebucketing procedure caused significant beam debunching in addition to amplifying debunching due to other mechanisms. At the end of a four hour store, debunched beam could account for approximately 30%-40% of the total beam intensity. Some of it will be in the abort gap. In order to minimize the risk of magnet quenching due to uncontrolled beam losses at the time of a beam dump, a combination of a fast transverse kicker and copper collimators were used to clean the abort gap. This report gives an overview of the gap cleaning procedure and the achieved performance

  20. Enhanced dilepton radiation at RHIC

    CERN Document Server

    Toia, Alberica

    2009-01-01

    Recently, there is growing evidence that a new state of matter is formed in Au+Au collisions at RHIC: a strongly coupled Quark Gluon Plasma of partonic degrees of freedom which develops a collective motion. Dilepton spectra are not affected by strong interaction and can therefore probe the whole time evolution of the collision. Thus they may be sensitive to the onset of deconfinement, chiral symmetry restoration, as well as the production of thermal photons. The PHENIX experiment measured the production of e+e− pairs in p+p and Au+Au collisions at . An enhanced dilepton yield in the mass range is measured. The excess increases faster with centrality than the number of participating nucleons, and is concentrated at . At higher pT the excess below 300 MeV/c2 has been related to an enhanced production of direct photons, possibly of thermal origin.

  1. Industrial production of RHIC magnets

    International Nuclear Information System (INIS)

    Anerella, M.D.; Fisher, D.H.; Sheedy, E.; McGuire, T.

    1996-01-01

    RHIC 8 cm aperture dipole magnets and quadrupole cold masses are being built for Brookhaven National Laboratory (BNL) by Northrop Grumman Corporation at a production rate of one dipole magnet and two quadrupole cold masses per day. This work was preceded by a lengthy Technology Transfer effort which is described elsewhere. This paper describes the tooling which is being used for the construction effort, the production operations at each workstation, and also the use of trend plots of critical construction parameters as a tool for monitoring performance in production. A report on the improvements to production labor since the start of the programs is also provided. The magnet and cold mass designs, and magnetic test results are described in more detail in a separate paper

  2. Superconducting Helical Snake Magnet for the AGS

    CERN Document Server

    Willen, Erich; Escallier, John; Ganetis, George; Ghosh, Arup; Gupta, Ramesh C; Harrison, Michael; Jain, Animesh K; Luccio, Alfredo U; MacKay, William W; Marone, Andrew; Muratore, Joseph F; Okamura, Masahiro; Plate, Stephen R; Roser, Thomas; Tsoupas, Nicholaos; Wanderer, Peter

    2005-01-01

    A superconducting helical magnet has been built for polarized proton acceleration in the Brookhaven AGS. This "partial Snake" magnet will help to reduce the loss of polarization of the beam due to machine resonances. It is a 3 T magnet some 1940 mm in magnetic length in which the dipole field rotates with a pitch of 0.2053 degrees/mm for 1154 mm in the center and a pitch of 0.3920 degrees/mm for 393 mm in each end. The coil cross-section is made of two slotted cylinders containing superconductor. In order to minimize residual offsets and deflections of the beam on its orbit through the Snake, a careful balancing of the coil parameters was necessary. In addition to the main helical coils, a solenoid winding was built on the cold bore tube inside the main coils to compensate for the axial component of the field that is experienced by the beam when it is off-axis in this helical magnet. Also, two dipole corrector magnets were placed on the same tube with the solenoid. A low heat leak cryostat was built so that t...

  3. Experts dismiss doomsday scenarios for RHIC

    CERN Multimedia

    Levi, B G

    2000-01-01

    A panel of particle physicists examining the possibility that operation of RHIC could generate blackholes or 'strangelets' which would consume ordinary matter, have declared that such scenarios are 'firmly excluded' (1 p).

  4. Advantages of polarization experiments at RHIC

    International Nuclear Information System (INIS)

    Underwood, D.G.

    1990-01-01

    We point out various spin experiments that could be done if the polarized beam option is pursued at RHIC. The advantages of RHIC for investigating several current and future physics problems are discussed. In particular, the gluon spin dependent structure function of the nucleon could be measured cleanly and systematically. Relevant experience developed in conjunction with the Fermilab Polarized Beam program is also presented. 8 refs., 2 tabs

  5. Chasing the unicorn: RHIC and the QGP

    International Nuclear Information System (INIS)

    Pisarski, Robert D.; Niels Bohr Institute, Copenhagen; J. W. Goethe Univ., Frankfurt

    2006-01-01

    At nonzero temperature, it is expected that QCD undergoes a phase transition to a deconfined, chirally symmetric phase, the Quark-Gluon Plasma (QGP). I review what we expect theoretically about this possible transition, and what we have learned from heavy ion experiments at RHIC. I argue that while there are unambiguous signals for qualitatively new behavior at RHIC, versus experiments at lower energies, that in detail, no simple theoretical model can explain all salient features of the data. (author)

  6. A NEW RELATIVE PROTON POLARIMETER FOR RHIC

    International Nuclear Information System (INIS)

    HUANG, H.; ALEKSEEV, I.; BUNCE, G.; BRUNER, N.; DESHPANDE, A.; GOTO, Y.; FIELDS, D.; IMAI, K.

    2001-01-01

    An innovative polarimeter based on proton carbon elastic scattering in the Coulomb Nuclear Interference (CNI) region has been installed and commissioned in the Blue ring of RHIC during the first RHIC polarized proton commissioning in September, 2000. The polarimeter consists of ultra-thin carbon targets and four silicon detectors. All elements are in a 1.6 meter vacuum chamber. This paper summarizes the polarimeter design issues and recent commissioning results

  7. Chasing the unicorn: RHIC and the QGP

    Energy Technology Data Exchange (ETDEWEB)

    Pisarski, Robert D. [Brookhaven National Lab., Upton, NY (United States). Nuclear Theory and High Energy Theory Nuclear Theory Groups; Niels Bohr Institute, Copenhagen (Denmark); J. W. Goethe Univ., Frankfurt (Germany). Frankfurt Institute for Advanced Study

    2006-03-15

    At nonzero temperature, it is expected that QCD undergoes a phase transition to a deconfined, chirally symmetric phase, the Quark-Gluon Plasma (QGP). I review what we expect theoretically about this possible transition, and what we have learned from heavy ion experiments at RHIC. I argue that while there are unambiguous signals for qualitatively new behavior at RHIC, versus experiments at lower energies, that in detail, no simple theoretical model can explain all salient features of the data. (author)

  8. COMMISSIONING CNI PROTON POLARIMETERS IN RHIC

    International Nuclear Information System (INIS)

    HUANG, H.; BRAVAR, A.; LI, Z.; MACKAY, W.W.; MAKDISI, Y.; RESCIA, S.; ROSER, T.; SURROW, B.; BUNCE, G.; DESHPANDE, A.; GOTO, Y.; ET AL

    2002-01-01

    Two polarimeters based on proton carbon elastic scattering in the Coulomb Nuclear Interference (CNI) region have been installed and commissioned in the Blue and Yellow rings of RHIC during the first RHIC polarized proton collider run. Each polarimeter consists of ultra-thin carbon targets and six silicon detectors. With newly developed wave form digitizers, they provide fast and reliable polarization information for both rings

  9. The dipole corrector magnets for the RHIC fast global orbit feedback system

    International Nuclear Information System (INIS)

    Thieberger, P.; Arnold, L.; Folz, C.; Hulsart, R.; Jain, A.; Karl, R.; Mahler, G.; Meng, W.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Ptitsyn, V.; Ritter, J.; Smart, L.; Tuozzolo, J.; White, J.

    2011-01-01

    The recently completed RHIC fast global orbit feedback system uses 24 small 'window-frame' horizontal dipole correctors. Space limitations dictated a very compact design. The magnetic design and modelling of these laminated yoke magnets is described as well as the mechanical implementation, coil winding, vacuum impregnation, etc. Test procedures to determine the field quality and frequency response are described. The results of these measurements are presented and discussed. A small fringe field from each magnet, overlapping the opposite RHIC ring, is compensated by a correction winding placed on the opposite ring's magnet and connected in series with the main winding of the first one. Results from measurements of this compensation scheme are shown and discussed.

  10. Serpentine Coil Topology for BNL Direct Wind Superconducting Magnets

    CERN Document Server

    Parker, Brett

    2005-01-01

    BNL direct wind technology, with the conductor pattern laid out without need for extra tooling (no collars, coil presses etc.) began with RHIC corrector production. RHIC patterns were wound flat and then wrapped on cylindrical support tubes. Later for the HERA-II IR magnets we improved conductor placement precision by winding directly on a support tube. To meet HERA-II space and field quality goals took sophisticated coil patterns, (some wound on tapered tubes). We denote such patterns, topologically equivalent to RHIC flat windings, "planar patterns." Multi-layer planar patterns run into trouble because it is hard to wind across existing turns and magnet leads get trapped at poles. So we invented a new "Serpentine" winding style, which goes around 360 degrees while the conductor winds back and forth on the tube. To avoid making solenoidal fields, we wind Serpentine layers in opposite handed pairs. With a Serpentine pattern each turn can have the same projection on the coil axis and integral field harmonics t...

  11. Design study of a normal conducting helical snake for AGS

    CERN Document Server

    Takano, Junpei; Okamura, Masahiro; Roser, Thomas; MacKay, William W; Luccio, Alfredo U; Takano, Koji

    2004-01-01

    A new normal conducting snake magnet is being fabricated for the Alternate Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL). In the Relativistic Heavy Ion Collider (RHIC) project, a superconducting type helical dipole magnets had been developed and it performed successfully in high-energy polarized proton acceleration. The new AGS helical snake has the same basic magnetic structure but is more complicated. To achieve no beam shift and no beam deflection in one magnetic device, helical pitches and rotating angles were carefully calculated. Compared to a superconducting magnet, a normal warm magnet must have a large cross- sectional area of conductors which make it difficult to design a magnet with large helical pitch. We developed a modified window frame structure to accommodate the large number of conductors. Its three dimensional magnetic field was simulated by using OPERA3D/TOSCA. 3 Refs.

  12. Snakes and spin rotators

    International Nuclear Information System (INIS)

    Lee, S.Y.

    1990-01-01

    The generalized snake configuration offers advantages of either shorter total snake length and smaller orbit displacement in the compact configuration or the multi-functions in the split configuration. We found that the compact configuration can save about 10% of the total length of a snake. On other hand, the spilt snake configuration can be used both as a snake and as a spin rotator for the helicity state. Using the orbit compensation dipoles, the spilt snake configuration can be located at any distance on both sides of the interaction point of a collider provided that there is no net dipole rotation between two halves of the snake. The generalized configuration is then applied to the partial snake excitation. Simple formula have been obtained to understand the behavior of the partial snake. Similar principle can also be applied to the spin rotators. We also estimate the possible snake imperfections are due to various construction errors of the dipole magnets. Accuracy of field error of better than 10 -4 will be significant. 2 refs., 5 figs

  13. Closed orbit analysis for RHIC

    International Nuclear Information System (INIS)

    Milutinovic, J.; Ruggiero, A.G.

    1989-01-01

    We examine the effects of four types of errors in the RHIC dipoles and quadrupoles on the on-momentum closed orbit in the machine. We use PATRIS both to handle statistically the effects of kick-modeled errors and to check the performance of the Fermilab correcting scheme in a framework of a more realistic modeling. On the basis of the accepted rms values of the lattice errors, we conclude that in about 40% of all studied cases the lattice must be to some extent pre-corrected in the framework of the so-called ''first turn around strategy,'' in order to get a closed orbit within the aperture limitations at all and, furthermore, for approximately 2/3 of the remaining cases we find that a single pass algorithm of the Fermilab scheme is not sufficient to bring closed orbit distortions down to acceptable levels. We have modified the scheme and have allowed repeated applications of the otherwise unchanged three bump method and in doing so we have been able to correct the orbit in a satisfactory manner. 4 refs., 2 figs., 3 tabs

  14. Snake evolution and prospecting of snake venom

    OpenAIRE

    Vonk, Freek Jacobus

    2012-01-01

    in this thesis I have shown that snakes have undergone multiple changes in their genome and embryonic development that has provided them with the variation to which natural selection could act. This thesis provides evidence for the variable mechanisms of venom gene evolution, which presumably is much more flexible than previously thought. But it also underscores the potential use of the many different types of snake venom toxins that could be screened for use against human disorders. And most...

  15. Proceedings of the symposium on RHIC detector R ampersand D

    International Nuclear Information System (INIS)

    Makdisi, Y.; Stevens, A.J.

    1991-01-01

    This report contains papers on the following topics: Development of Analog Memories for RHIC Detector Front-end Electronic Systems; Monolithic Circuit Development for RHIC at Oak Ridge National Laboratory; Highly Integrated Electronics for the STAR TPC; Monolithic Readout Circuits for RHIC; New Methods for Trigger Electronics Development; Neurocomputing methods for Pattern Recognition in Nuclear Physics; The Development of a Silicon Multiplicity Detector System; A Transition Radiation Detector for RHIC Featuring Accurate

  16. The Complexity of Snake

    OpenAIRE

    De Biasi, Marzio; Ophelders, Tim

    2016-01-01

    Snake and Nibbler are two well-known video games in which a snake slithers through a maze and grows as it collects food. During this process, the snake must avoid any collision with its tail. Various goals can be associated with these video games, such as avoiding the tail as long as possible, or collecting a certain amount of food, or reaching some target location. Unfortunately, like many other motion-planning problems, even very restricted variants are computationally intractable. In parti...

  17. BROOKHAVEN: Major detectors for RHIC under construction

    International Nuclear Information System (INIS)

    Ludlam, Thomas W.

    1994-01-01

    On March 9-10, a cost and schedule review at Brookhaven verified construction readiness for the PHENIX detector (May 1993, page 10). PHENIX thus joins STAR (Solenoidal Tracking at RHIC - November 1991, page 17), whose construction plan was ratified in January 1993, as a major detector to take data when the RHIC heavy ion collider is completed in mid-1999. The goal of both detectors is to search for the transition from ordinary nuclear matter to a new state of matter consisting of (momentarily) unconfined quarks and gluons. This transition to a ''quark-gluon plasma'' (QGP) is predicted to occur under extreme conditions of temperature and energy density, as is likely to be the case in the collision of heavy ions of sufficient energy. RHIC is expected to produce the highest energy densities ever observed on the nuclear scale

  18. Estimation of collective instabilities in RHIC

    International Nuclear Information System (INIS)

    MacKay, W.W.; Blaskiewicz, M.; Deng, D.; Mane, V.; Peggs, S.; Ratti, A.; Rose, J.; Shea, T.J.; Wei, J.

    1995-01-01

    The authors have estimated the broadband impedance in RHIC to be |Z/n| +79 ions at transition with an estimated 10% growth in emittance for Z/n = 1.5 Ω. They summarize the sources of broad and narrow band impedances in RHIC and investigate the multibunch instability limits throughout the machine cycle. The largest contribution to the broadband impedance comes from the abort and injection kickers. Since RHIC is designed to accelerate fully stripped ions from H + up to Au +79 they give results for both protons and gold ions; other ions should give results somewhere between these two extremes. All ion species are expected to be stable during storage. At lower energies damping systems and chromaticity corrections will limit any growth to acceptable levels during the short time it takes to inject and accelerate the beams

  19. RHIC Beam Loss Monitor System Initial Operation

    International Nuclear Information System (INIS)

    Witkover, R. L.; Michnoff, R. J.; Geller, J. M.

    1999-01-01

    The RHIC Beam Loss Monitor (BLM) System is designed to prevent beam loss quenching of the superconducting magnets, and acquire loss data. Four hundred ion chambers are located around the rings to detect losses. The required 8-decade range in signal current is compressed using an RC pre-integrator ahead of a low current amplifier. A beam abort may be triggered if fast or slow losses exceed programmable threshold levels. A micro-controller based VME module sets references and gains and reads trip status for up to 64 channels. Results obtained with the detectors in the RHIC Sextant Test and the prototype electronics in the AGS-to-RHIC (AtR) transfer line are presented along with the present status of the system

  20. RHIC BPM System Modifications and Performance

    CERN Document Server

    Satogata, Todd; Cameron, Peter; Cerniglia, Phil; Cupolo, John; Curcio, Anthony J; Dawson, William C; Degen, Christopher; Gullotta, Justin; Mead, Joe; Michnoff, Robert; Russo, Thomas; Sikora, Robert

    2005-01-01

    The RHIC beam position monitor (BPM) system provides independent average orbit and turn-by-turn (TBT) position measurements. In each ring, there are 162 measurement locations per plane (horizontal and vertical) for a total of 648 BPM planes in the RHIC machine. During 2003 and 2004 shutdowns, BPM processing electronics were moved from the RHIC tunnel to controls alcoves to reduce radiation impact, and the analog signal paths of several dozen modules were modified to eliminate gain-switching relays and improve signal stability. This paper presents results of improved system performance, including stability for interaction region and sextupole beam-based alignment efforts. We also summarize performance of improved million-turn TBT acquisition channels for nonlinear dynamics and echo studies.

  1. Implementation of Ramp Control in RHIC

    International Nuclear Information System (INIS)

    Kewisch, J.

    1999-01-01

    After the injection of beam into RHIC the beam energy is ramped from 10.8 GeV/u to 108 GeV/u and the beta function of the interaction points is reduced from 10 meters to 1 meter. The set points for magnet power supplies and RF cavities is changed during such ramps in concert. A system of Wave Form Generators (WFGs), interconnected by a Real Time Data Link (RTDL) and Event Link is used to control these devices. RHIC ramps use a two level system of WFGs: one transmits the beam energy and a ''pseudo time'' variable as functions of time via RTDL; the other calculates the device set points as functions of these RTDL variables. Energy scaling, saturation correction and the wiring of interaction region quadruples is performed on the second level. This report describes the configuration and implementation of the software, firmware and hardware of the RHIC ramp system

  2. Beam Induced Pressure Rise at RHIC

    CERN Document Server

    Zhang, S Y; Bai, Mei; Blaskiewicz, Michael; Cameron, Peter; Drees, Angelika; Fischer, Wolfram; Gullotta, Justin; He, Ping; Hseuh Hsiao Chaun; Huang, Haixin; Iriso, Ubaldo; Lee, Roger C; Litvinenko, Vladimir N; MacKay, William W; Nicoletti, Tony; Oerter, Brian; Peggs, Steve; Pilat, Fulvia Caterina; Ptitsyn, Vadim; Roser, Thomas; Satogata, Todd; Smart, Loralie; Snydstrup, Louis; Thieberger, Peter; Trbojevic, Dejan; Wang, Lanfa; Wei, Jie; Zeno, Keith

    2005-01-01

    Beam induced pressure rise in RHIC warm sections is currently one of the machine intensity and luminosity limits. This pressure rise is mainly due to electron cloud effects. The RHIC warm section electron cloud is associated with longer bunch spacings compared with other machines, and is distributed non-uniformly around the ring. In addition to the countermeasures for normal electron cloud, such as the NEG coated pipe, solenoids, beam scrubbing, bunch gaps, and larger bunch spacing, other studies and beam tests toward the understanding and counteracting RHIC warm electron cloud are of interest. These include the ion desorption studies and the test of anti-grazing ridges. For high bunch intensities and the shortest bunch spacings, pressure rises at certain locations in the cryogenic region have been observed during the past two runs. Beam studies are planned for the current 2005 run and the results will be reported.

  3. The RHIC real time data link system

    International Nuclear Information System (INIS)

    Hartmann, H.

    1997-01-01

    The RHIC Real Time Data Link (RTDL) System distributes to all locations around the RHIC ring machine parameters of general interest to accelerator systems and users. The system, along with supporting host interface, is centrally located. The RTDL System is comprised of two module types: the Encoder Module (V105) and the Input Module (V106). There is only one V105 module, but many (up to 128) Input Modules. Multiple buffered outputs are provided for use locally or for retransmission to other RHIC equipment locations. Machine parameters are generated from the V115 Waveform Generator Module (WFG) or from machine hardware and coupled directly through a fiber optic serial link to one of the V106 input channels

  4. Minimization of spin tune spread by matching dispersion prime at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Kewisch, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-08-31

    At RHIC, the spin polarization is preserved with a pair of Siberian snakes on the oppo- site sides in each ring. The polarized proton beam with finite spin tune spread might cross spin resonances multiple times in two cases, one is when beam going through strong spin intrinsic resonances during acceleration, the other is when sweeping spin flipper’ frequency across the spin tune to flip the direction of spin polarization. The consequence is loss of spin polarization in both cases. Therefore, a scheme of min- imizing the spin tune spread by matching the dispersion primes at the two snakes was introduced based on the fact that the spin tune spread is proportional to the difference of dispersion primes at the two snakes. The scheme was implemented at fixed energies for the spin flipper study and during beam acceleration for better spin polarization transmission efficiency. The effect of minimizing the spin tune spread by matching the dispersion primes was observed and confirmed experimentally. The principle of minimizing the spin tune spread by matching the dispersion primes, the impact on the beam optics, and the effect of a narrower spin tune spread are presented in this report.

  5. Experience with split transition lattices at RHIC

    International Nuclear Information System (INIS)

    Montag, C.; Tepikian, S.; Blaskiewicz, M.; Brennan, J.M.

    2010-01-01

    During the acceleration process, heavy ion beams in RHIC cross the transition energy. When RHIC was colliding deuterons and gold ions during Run-8, lattices with different integer tunes were used for the two rings. This resulted in the two rings crossing transition at different times, which proved beneficial for the 'Yellow' ring, the RF system of which is slaved to the 'Blue' ring. For the symmetric gold-gold run in FY2010, lattices with different transition energies but equal tunes were implemented. We report the optics design concept as well as operational experience with this configuration.

  6. Heavy nuclei, from RHIC to the cosmos

    International Nuclear Information System (INIS)

    Klein, Spencer R.

    2003-01-01

    Ultra-relativistic heavy ion collisions produce a high-temperature, thermalized system that may mimic the conditions present shortly after the big bang. This writeup will given an overview of early results from the Relativistic Heavy Ion Collider (RHIC), and discuss what we have learned about hot, strongly interacting nuclear systems. The thermal and chemical composition of the system will be discussed, along with observables that are sensitive to the early evolution of the system. I will also discuss the implications of the RHIC results for cosmic ray air showers

  7. A prototype ionization profile monitor for RHIC

    International Nuclear Information System (INIS)

    Connolly, R.; Cameron, P.; Ryan, W.

    1997-01-01

    Transverse beam profiles in the Relativistic Heavy-Ion Collider (RHIC) will be measured with ionization profile monitors (IPM's). Each IPM collects and measures the distribution of electrons in the beamline resulting from residual gas ionization during bunch passage. The electrons are swept transversely from the beamline and collected on strip anodes oriented parallel to the beam axis. At each bunch passage the charge pulses are amplified, integrated, and digitized for display as a profile histogram. A prototype detector was tested in the injection line during the RHIC Sextant Test. This paper describes the detector and gives results from the beam tests

  8. The RHIC transfer line cable database

    International Nuclear Information System (INIS)

    Scholl, E.H.; Satogata, T.

    1995-01-01

    A cable database was created to facilitate and document installation of cables and wiring in the RHIC project, as well as to provide a data source to track possible wiring and signal problems. The eight tables of this relational database, currently implemented in Sybase, contain information ranging from cable routing to attenuation of individual wires. This database was created in a hierarchical scheme under the assumption that cables contain wires -- each instance of a cable has one to many wires associated with it. This scheme allows entry of information pertinent to individual wires while only requiring single entries for each cable. Relationships to other RHIC databases are also discussed

  9. Summary of the RHIC Retreat 2008

    Energy Technology Data Exchange (ETDEWEB)

    Pilat,F.; Brennan, M.; Brown, K.; Fischer, W.; Montag, C.

    2008-08-01

    The main goal of the RHIC Retreat is to review last run's performance and prepare for the next. As always though we also discussed the longer term goals and plans for the facility to put the work in perspective and in the right priority. A straw-man plan for the facility was prepared for the DOE that assumes 30 cryoweek and running 2 species per year. The plan outlines RHIC operations for 2008-2012 and integrates well accelerator and detector upgrades to optimize the physics output with high luminosities. The plans includes guidance from the PAC and has been reviewed by DOE.

  10. Global Decoupling on the RHIC Ramp

    CERN Document Server

    Luo, Yun; Della Penna, Al; Fischer, Wolfram; Laster, Jonathan S; Marusic, Al; Pilat, Fulvia Caterina; Roser, Thomas; Trbojevic, Dejan

    2005-01-01

    The global betatron decoupling on the ramp is an important issue for the operation of the Relativistic Heavy Ion Collider (RHIC). In the polarized proton run, the betatron tunes are required to keep almost constant on the ramp to avoid spin resonance line crossing and the beam polarization loss. Some possible correction schemes on the ramp, like three-ramp correction, the coupling amplitude modulation and the coupling phase modulaxtion, have been found. The principles of these schemes are shortly reviewed and compared. Operational results of their applications on the RHIC ramps are given.

  11. Summary of the RHIC Retreat 2008

    International Nuclear Information System (INIS)

    Pilat, F.; Brennan, M.; Brown, K.; Fischer, W.; Montag, C.

    2008-01-01

    The main goal of the RHIC Retreat is to review last run's performance and prepare for the next. As always though we also discussed the longer term goals and plans for the facility to put the work in perspective and in the right priority. A straw-man plan for the facility was prepared for the DOE that assumes 30 cryoweek and running 2 species per year. The plan outlines RHIC operations for 2008-2012 and integrates well accelerator and detector upgrades to optimize the physics output with high luminosities. The plans includes guidance from the PAC and has been reviewed by DOE

  12. Dilepton Production at Fermilab and RHIC

    International Nuclear Information System (INIS)

    Peng, J.C.; McGaughey, P.L.; Moss, J.M.

    1999-01-01

    Some recent results from several fixed-target dimuon production experiments at Fermilab are presented. In particular, we discuss the use of Drell-Yan data to determine the flavor structure of the nucleon sea, as well as to deduce the energy-loss of partons traversing nuclear medium. Future dilepton experiments at RHIC could shed more light on the flavor asymmetry and possible charge-symmetry-violation of the nucleon sea. Clear evidence for scaling violation in the Drell-Yan process could also be revealed at RHIC

  13. RHIC ABORT KICKER WITH REDUCED COUPLING IMPEDANCE

    International Nuclear Information System (INIS)

    HAHN, H.; DAVINO, D.

    2002-01-01

    Kicker magnets typically represent the most important contributors to the transverse impedance budget of accelerators and storage rings. Methods of reducing the impedance value of the SNS extraction kicker presently under construction and, in view of a future performance upgrade, that of the RHIC abort kicker have been thoroughly studied at this laboratory. In this paper, the investigation of a potential improvement from using ferrite different from the BNL standard CMD5005 is reported. Permeability measurements of several ferrite types have been performed. Measurements on two kicker magnets using CMD5005 and C2050 suggest that the impedance of a magnet without external resistive damping, such as the RHIC abort kicker, would benefit

  14. PROPOSAL FOR AN EBIS BASED RHIC PREINJECTOR.

    Energy Technology Data Exchange (ETDEWEB)

    ALESSI,J.G.; BEEBE,E.; KPONOU,A.; PIKIN,A.; PRELEC,K.; RAPARIA,D.; RITTER,J.; ZHANG,S.Y.

    2000-11-06

    A proposed new heavy ion preinjector for RHIC is described. The progress made at BNL on the development of an Electron Beam Ion Source (EBIS) has increased our confidence that one can build a preinjector meeting RHIC requirements using an EBIS producing intermediate charge state heavy ions. A new RFQ and Linac will be required to accelerate beams from this source to an energy sufficient for injection into the AGS Booster. These are both straightforward devices, very similar to ones already in operation at other laboratories. Injection into the Booster will occur at the same location as the existing heavy ion injection from the Tandem Van de Graaff.

  15. SIMULATION OF PARTICLE SPECTRA AT RHIC

    International Nuclear Information System (INIS)

    KAHANA, D.E.; KAHANA, S.H.

    2001-01-01

    A purely hadronic simulation is performed of the recently reported data from PHOBOS at energies of √s = 56, 130 GeV using the relativistic heavy ion cascade LUCIFER which had previously given a good description of the NA49 inclusive spectra at √s = 17.2 GeV/A. The results compare well with these early measurements at RHIC and indeed successfully predict the increase in multiplicity now seen by PHOBOS and the other RHIC detectors at the nominal maximum energy of √s = 200 GeV/A, suggesting that evidence for quark-gluon matter remains elusive

  16. A prototype ionization profile monitor for RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Connolly, R.; Cameron, P.; Ryan, W. [and others

    1997-07-01

    Transverse beam profiles in the Relativistic Heavy-Ion Collider (RHIC) will be measured with ionization profile monitors (IPM`s). Each IPM collects and measures the distribution of electrons in the beamline resulting from residual gas ionization during bunch passage. The electrons are swept transversely from the beamline and collected on strip anodes oriented parallel to the beam axis. At each bunch passage the charge pulses are amplified, integrated, and digitized for display as a profile histogram. A prototype detector was tested in the injection line during the RHIC Sextant Test. This paper describes the detector and gives results from the beam tests.

  17. Iron saturation control in RHIC dipole magnets

    International Nuclear Information System (INIS)

    Thompson, P.A.; Gupta, R.C.; Kahn, S.A.; Hahn, H.; Morgan, G.H.; Wanderer, P.J.; Willen, E.

    1991-01-01

    The Relativistic Heavy Ion Collider (RHIC) will require 360 dipoles of 80 mm bore. This paper discusses the field perturbations produced by the saturation of the yoke iron. Changes have been made to the yoke to reduce these perturbations, in particular, decapole -4 . Measurements and calculations for 6 series of dipole magnets are presented. 2 refs., 2 figs., 1 tab

  18. EVENT GENERATOR FOR RHIC SPIN PHYSICS

    International Nuclear Information System (INIS)

    SAITO, N.; SCHAEFER, A.

    1999-01-01

    This volume archives the reports from the RIKEN BNL Research Center workshop on ''Event Generator for RHIC Spin Physics II'' held during the week March 15, 1999 at Brookhaven National Laboratory. It was the second meeting on the subject following a first one in last September. This workshop has been initiated to establish a firm collaboration between theorists and experimentalists involved in RHIC spin physics with the aim of developing a reliable, high-precision event generator for RHIC spin physics. Needless to say, adequate event generators are indispensable tools for high energy physics programs in general, especially in the process of: planning the experimental programs; developing algorithms to extract the physics signals of interest; estimating the background in the extracted results, and connecting the final particle kinematics to the fundamental i.e. partonic level processes. Since RHIC is the first polarized collider, dedicated efforts are required to obtain a full-fledged event generator which describes spin dependent reactions in great detail

  19. RHIC Proton Luminosity and Polarization Improvement

    International Nuclear Information System (INIS)

    Zhang, S. Y.

    2014-01-01

    The RHIC proton beam polarization can be improved by raising the Booster scraping, which also helps to reduce the RHIC transverse emittance, and therefore to improve the luminosity. By doing this, the beam-beam effect would be enhanced. Currently, the RHIC working point is constrained between 2/3 and 7/10, the 2/3 resonance would affect intensity and luminosity lifetime, and the working point close to 7/10 would enhance polarization decay in store. Run 2013 shows that average polarization decay is merely 1.8% in 8 hours, and most fills have the luminosity lifetime better than 14 hours, which is not a problem. Therefore, even without beam-beam correction, there is room to improve for RHIC polarization and luminosity. The key to push the Booster scraping is to raise the Booster input intensity; for that, two approaches can be used. The first is to extend the LINAC tank 9 pulse width, which has been successfully applied in run 2006. The second is to raise the source temperature, which has been successfully applied in run 2006 and run 2012.

  20. A study of RHIC crystal collimation

    International Nuclear Information System (INIS)

    Trbojevic, D.; Harrison, M.; Parker, B.; Thompson, P.; Stevens, A.; Biryukov, V.; Mokhov, N.; Drozhdin, A.

    1998-01-01

    The Relativistic Heavy Ion Collider (RHIC) will experience increasing longitudinal and transverse heavy ion emittances, mostly due to intra-beam scattering (IBS). The experiments in RHIC are expected to not only have reduced luminosities due to IBS but also background caused by beam halo. Primary betatron collimators will be used to remove the large amplitude particles. The efficiency of the primary collimator in RHIC strongly depends on the alignment of the jaws which needs to be within about ten micro-radians for the optimum conditions. As proposed by V. biryukov bent crystals could be used to improve the efficiency of an existing collimation system by installing them upstream of the collimator jaws. Bent crystals have been successfully used in SPS, Protvino and Fermilab for extraction of the beam particles channeled through them. This study examines possible improvements of the primary collimator system for heavy ions at RHIC by use of bent crystals. Bent crystals will reduce the collimator jaws alignment requirement and will increase collimator efficiency thereby reducing detector background

  1. Brahms Experiment at RHIC Day-1 Physics

    International Nuclear Information System (INIS)

    Videbaek, Flemming

    1999-01-01

    The BRAHMS experiment is designed to measure semi-inclusive spectra of charged hadron over a wide range of rapidity. It will yield information on particle production, both at central rapidity and in the baryon rich fragmentation region. The physics plans for measurements in the first year of running at RHIC are discussed

  2. Snake evolution and prospecting of snake venom

    NARCIS (Netherlands)

    Vonk, Freek Jacobus

    2012-01-01

    in this thesis I have shown that snakes have undergone multiple changes in their genome and embryonic development that has provided them with the variation to which natural selection could act. This thesis provides evidence for the variable mechanisms of venom gene evolution, which presumably is

  3. Optimization of multiwire coil ends having 45 degree bends

    International Nuclear Information System (INIS)

    Morgan, G.H.

    1989-01-01

    Multiwire is the name of a proprietary process for affixing small diameter wires to a flat substrate using digitally controlled machinery. It is currently being used to wind trim coils for the SSC dipoles on a flexible substrate which is wrapped around the beam tube. It is proposed for making multipole coils for the Corrector, a regular arc magnet in each half-cell of the Relativistic Heavy Ion Collider (RHIC). The current Multiwire process does not permit a change in direction of the wire other than 45 degree. The present paper answers the question of whether the 45 degree bends in the flattened coil can be located along straight lines in such a way as to eliminate or reduce higher harmonics in the ends. The more general question of bends located along curves is not addressed

  4. Optimization of multiwire coil ends having 45 degree bends

    International Nuclear Information System (INIS)

    Morgan, G.H.

    1988-01-01

    Multiwire is the name of a proprietary process for affixing small diameter wires to a flat substrate using digitally controlled machinery. It is currently being used to wind trim coils for the SSC dipoles on a flexible substrate which is wrapped around the beam tube. It is proposed for making multipole coils for the Corrector, a regular arc magnet in each half-cell of the Relativistic Heavy Ion Collider (RHIC). The current Multiwire process does not permit a change in direction of the wire other than 45 degree. The present paper answers the question of whether the 45 degree bends in the flattened coil can be located along straight lines in such a way as to eliminate or reduce higher harmonics in the ends. The more general question of bends located along curves is not addressed. 3 refs., 3 figs., 2 tabs

  5. Beam Based Measurements of Field Multipoles in the RHIC Low Beta Insertions and Extrapolation of the Method to the LHC

    CERN Document Server

    Koutchouk, Jean-Pierre; Ptitsyn, V I

    2001-01-01

    The multipolar content of the dipoles and quadrupoles is known to limit the stability of the beam dynamics in super-conducting machines like RHIC and even more in LHC. The low-beta quadrupoles are thus equipped with correcting coils up to the dodecapole order. The correction is planned to rely on magnetic measurements. We show that a relatively simple method allows an accurate measurement of the multipolar field aberrations using the beam. The principle is to displace the beam in the non-linear fields by local closed orbit bumps and to measure the variation of sensitive beam observable. The resolution and robustness of the method are found appropriate. Experimentation at RHIC showed clearly the presence of normal and skew sextupolar field components in addition to a skew quadrupolar component in the interaction regions. Higher-order components up to decapole order appear as well.

  6. Predation upon hatchling dinosaurs by a new snake from the late Cretaceous of India.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Wilson

    2010-03-01

    Full Text Available Derived large-mouthed snakes (macrostomatans possess numerous specializations in their skull and lower jaws that allow them to consume large vertebrate prey. In contrast, basal snakes lack these adaptations and feed primarily on small prey items. The sequence of osteological and behavioral modifications involved in the evolution of the macrostomatan condition has remained an open question because of disagreement about the origin and interrelationships of snakes, the paucity of well-preserved early snake fossils on many continental landmasses, and the lack of information about the feeding ecology of early snakes. We report on a partial skeleton of a new 3.5-m-long snake, Sanajeh indicus gen. et sp. nov., recovered from Upper Cretaceous rocks of western India. S. indicus was fossilized in association with a sauropod dinosaur egg clutch, coiled around an egg and adjacent to the remains of a ca. 0.5-m-long hatchling. Multiple snake-egg associations at the site strongly suggest that S. indicus frequented nesting grounds and preyed on hatchling sauropods. We interpret this pattern as "ethofossil" preservation of feeding behavior. S. indicus lacks specializations of modern egg-eaters and of macrostomatans, and skull and vertebral synapomorphies place it in an intermediate position in snake phylogeny. Sanajeh and its large-bodied madtsoiid sister taxa Yurlunggur camfieldensis and Wonambi naracoortensis from the Neogene of Australia show specializations for intraoral prey transport but lack the adaptations for wide gape that characterize living macrostomatan snakes. The Dholi Dungri fossils are the second definitive association between sauropod eggs and embryonic or hatchling remains. New fossils from western India provide direct evidence of feeding ecology in a Mesozoic snake and demonstrate predation risks for hatchling sauropod dinosaurs. Our results suggest that large body size and jaw mobility afforded some non-macrostomatan snakes a greater

  7. Pharmacokinetics of Snake Venom

    OpenAIRE

    Suchaya Sanhajariya; Stephen B. Duffull; Geoffrey K. Isbister

    2018-01-01

    Understanding snake venom pharmacokinetics is essential for developing risk assessment strategies and determining the optimal dose and timing of antivenom required to bind all venom in snakebite patients. This review aims to explore the current knowledge of snake venom pharmacokinetics in animals and humans. Literature searches were conducted using EMBASE (1974–present) and Medline (1946–present). For animals, 12 out of 520 initially identified studies met the inclusion criteria. In general, ...

  8. Reproductive strategies in snakes.

    OpenAIRE

    Shine, Richard

    2003-01-01

    Snakes of both sexes display remarkable flexibility and diversity in their reproductive tactics. Many features of reproduction in female snakes (such as reproductive mode and frequency, seasonality and multiple mating) allow flexible maternal control. For example, females can manipulate not only the genotypes of their offspring (through mate choice or enhanced sperm competition) but also the phenotypes of their offspring (through allocation 'decisions', behavioural and physiological thermoreg...

  9. Conception of Brownian coil

    OpenAIRE

    Zhang, Jiayuan

    2018-01-01

    This article proposes a conception of Brownian coil. Brownian coil is a tiny coil with the same size of pollen. Once immersed into designed magnetic field and liquid, the coil will be moved and deformed macroscopically, due to the microscopic thermodynamic molecular collisions. Such deformation and movement will change the magnetic flux through the coil, by which an ElectroMotive Force (EMF) is produced. In this work, Brownian heat exchanger and Brownian generator are further designed to tran...

  10. First turn around strategy for RHIC

    International Nuclear Information System (INIS)

    Milutinovic, J.; Ruggiero, A.G.

    1991-01-01

    The authors present a strategy for achieving the so-called first turn around in RHIC. The strategy is based on the same method proposed to correct a distorted closed orbit in RHIC, i.e. on a generalization of the local three-bump method. They found out that the method is very effective in passing the beam through a non-ideal, insufficiently known, machine. The perturbed lattice was generated by the code PATRIS, which was also adapted to control the newly developed software. In ten distributions of errors the software was capable of passing the beam through in 2-3 injection attempts, at full sextupole strength. It was also determined that once the beam makes the first turn around and all the correctors are energized, it stays in the machine for at least several hundred turns

  11. Adjusting the IP $\\beta$ Functions in RHIC

    CERN Document Server

    Wittmer, W; Pilat, F; Ptitsyn, V; Van Zeijts, J

    2004-01-01

    The beta functions at the IP can be adjusted without perturbation of other optics functions via several approaches. In this paper we describe a scheme based on a vector knob, which assigns fixed values to the different tuning quadrupoles and scales them by a common multiplier. The values for the knob vector were calculated for a lattice without any errors using MADX. Previous studies for the LHC [1] have shown that this approach can meet the design goals. A specific feature of the RHIC lattice is the nested power supply system. To cope with the resulting problems a detailed response matrix analysis has been carried out and different sets of knobs were calculated and compared. The knobs were tested at RHIC during the 2004 run and preliminary results are discussed. Simultaneously a new approach to measure the beam sizes of both colliding beams at the IP, based on the tunability provided by the knobs, was developed and tested.

  12. Ferrite HOM Absorber for the RHIC ERL

    Energy Technology Data Exchange (ETDEWEB)

    Hahn,H.; Choi, E.M.; Hammons, L.

    2008-10-01

    A superconducting Energy Recovery Linac is under construction at Brookhaven National Laboratory to serve as test bed for RHIC upgrades. The damping of higher-order modes in the superconducting five-cell cavity for the Energy-Recovery linac at RHIC is performed exclusively by two ferrite absorbers. The ferrite properties have been measured in ferrite-loaded pill box cavities resulting in the permeability values given by a first-order Debye model for the tiled absorber structure and an equivalent permeability value for computer simulations with solid ring dampers. Measured and simulated results for the higher-order modes in the prototype copper cavity are discussed. First room-temperature measurements of the finished niobium cavity are presented which confirm the effective damping of higher-order modes in the ERL. by the ferrite absorbers.

  13. Elliptic flow and incomplete equilibration at RHIC

    CERN Document Server

    Bhalerao, R S; Borghini, N; Ollitrault, Jean Yves

    2005-01-01

    We argue that RHIC data, in particular those on the anisotropic flow coefficients v_2 and v_4, suggest that the matter produced in the early stages of nucleus-nucleus collisions is incompletely thermalized. We interpret the parameter (1/S)(dN/dy), where S is the transverse area of the collision zone and dN/dy the multiplicity density, as an indicator of the number of collisions per particle at the time when elliptic flow is established, and hence as a measure of the degree of equilibration. This number serves as a control parameter which can be varied experimentally by changing the system size, the centrality or the beam energy. We provide predictions for Cu-Cu collisions at RHIC as well as for Pb-Pb collisions at the LHC.

  14. eRHIC ERL modeling in Zgoubi

    International Nuclear Information System (INIS)

    Meot, F.; Brooks, S.; Hao, Y.; Jing, Y.; Ptitsyn, V.; Trbojevic, D.; Tsoupas, N.

    2016-01-01

    This Note discusses on-going work regarding the modeling of eRHIC ERL in the ray-tracing code Zgoubi. The various pieces of the recirculator puzzle, their optical properties and their assemblage into an operational input data file in are addressed. The Note reports in particular on preparatory stages toward extensive end-to-end 6D polarized electron bunch transport simulations, which yield methods, as well a series of preliminary qualitative outcomes, discussed as well.

  15. DESCRIPTION OF THE RHIC SEQUENCER SYSTEM

    International Nuclear Information System (INIS)

    DOTTAVIO, T.; FRAK, B.; MORRIS, J.; SATOGATA, T.; VAN ZEIJTS, J.

    2001-01-01

    The movement of the Relativistic Heavy Ion Collider (RHIC) through its various states (eg. injection, acceleration, storage, collisions) is controlled by an application called the Sequencer. This program orchestrates most magnet and instrumentation systems and is responsible for the coordinated acquisition and saving of data from various systems. The Sequencer system, its software infrastructure, support programs, and the language used to drive it are discussed in this paper. Initial operational experience is also described

  16. Source of second order chromaticity in RHIC

    International Nuclear Information System (INIS)

    Luo, Y.; Gu, X.; Fischer, W.; Trbojevic, D.

    2011-01-01

    In this note we will answer the following questions: (1) what is the source of second order chromaticities in RHIC? (2) what is the dependence of second order chromaticity on the on-momentum β-beat? (3) what is the dependence of second order chromaticity on β* at IP6 and IP8? To answer these questions, we use the perturbation theory to numerically calculate the contributions of each quadrupole and sextupole to the first, second, and third order chromaticities.

  17. ANALYSIS OF AVAILABILITY AND RELIABILITY IN RHIC OPERATIONS

    International Nuclear Information System (INIS)

    PILAT, F.; INGRASSIA, P.; MICHNOFF, R.

    2006-01-01

    RHIC has been successfully operated for 5 years as a collider for different species, ranging from heavy ions including gold and copper, to polarized protons. We present a critical analysis of reliability data for RHIC that not only identifies the principal factors limiting availability but also evaluates critical choices at design times and assess their impact on present machine performance. RHIC availability data are typical when compared to similar high-energy colliders. The critical analysis of operations data is the basis for studies and plans to improve RHIC machine availability beyond the 50-60% typical of high-energy colliders

  18. Conceptual design of a quadrupole magnet for eRHIC

    Energy Technology Data Exchange (ETDEWEB)

    Witte, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    eRHIC is a proposed upgrade to the existing Relativistic Heavy Ion Collider (RHIC) hadron facility at Brookhaven National Laboratory, which would allow collisions of up to 21 GeV polarized electrons with a variety of species from the existing RHIC accelerator. eRHIC employs an Energy Recovery Linac (ERL) and an FFAG lattice for the arcs. The arcs require open-midplane quadrupole magnets of up to 30 T/m gradient of good field quality. In this paper we explore initial quadrupole magnet design concepts based on permanent magnetic material which allow to modify the gradient during operation.

  19. Analysis of RHIC beam dump pre-fires

    International Nuclear Information System (INIS)

    Zhang, W.; Ahrens, L.; Fischer, W.; Hahn, H.; Mi, J.; Sandberg, J.; Tan, Y.

    2011-01-01

    It has been speculated that the beam may cause instability of the RHIC Beam Abort Kickers. In this study, we explore the available data of past beam operations, the device history of key modulator components, and the radiation patterns to examine the correlations. The RHIC beam abort kicker system was designed and built in the 90's. Over last decade, we have made many improvements to bring the RHIC beam abort kicker system to a stable operational state. However, the challenge continues. We present the analysis of the pre-fire, an unrequested discharge of kicker, issues which relates to the RHIC machine safety and operational stability.

  20. QCD and Heavy Ions RHIC Overview

    CERN Document Server

    Granier de Cassagnac, Raphael

    2010-01-01

    Nowadays, the most violent heavy ion collisions available to experimental study occur at the Relativistic Heavy Ion Collider (RHIC) of the Brookhaven National Laboratory. There, gold ions collide at psNN = 200 GeV. The early and most striking RHIC results were summarised in 2005 by its four experiments, BRAHMS, PHENIX, PHOBOS and STAR, in their so-called white papers [1, 2, 3, 4] that will be largely referenced thereafter. Beyond and after this, a wealth of data has been collected and analysed, providing additional information about the properties of the matter created at RHIC. It is categorically impossible to give a comprehensive review of these results in a 20 minutes talk or a 7 pages report. Here, I have made a selection of some of the most striking or intriguing signatures: jet quenching in Section 2, quarkonia suppressions in Section 3 and thermal photons in Section 4. A slightly longer and older version of this review can be found in [5]. Some updates are given here, as well as emphasis on new probes ...

  1. RHIC beam loss monitor system design

    International Nuclear Information System (INIS)

    Witkover, R.; Zitvogel, E.; Michnoff, R.

    1997-01-01

    The Beam Loss Monitor (BLM) System is designed to prevent the quenching of RHIC magnets due to beam loss, provide quantitative loss data, and the loss history in the event of a beam abort. The system uses 400 ion chambers of a modified Tevatron design. To satisfy fast (single turn) and slow (100 msec) loss beam criteria and provide sensitivity for studies measurements, a range of over 8 decades is needed. An RC pre-integrator reduces the dynamic range for a low current amplifier. This is digitized for data logging. The output is also applied to an analog multiplier which compensates the energy dependence, extending the range of the abort comparators. High and low pass filters separate the signal to dual comparators with independent programmable trip levels. Up to 64 channels, on 8 VME boards, are controlled by a micro-controller based VME module, decoupling it from the front-end computer (FEC) for real-time operation. Results with the detectors in the RHIC Sextant Test and the electronics in the AGS-to-RHIC (AtR) transfer line will be presented

  2. RHIC spin flipper AC dipole controller

    Energy Technology Data Exchange (ETDEWEB)

    Oddo, P.; Bai, M.; Dawson, C.; Gassner, D.; Harvey, M.; Hayes, T.; Mernick, K.; Minty, M.; Roser, T.; Severino, F.; Smith, K.

    2011-03-28

    The RHIC Spin Flipper's five high-Q AC dipoles which are driven by a swept frequency waveform require precise control of phase and amplitude during the sweep. This control is achieved using FPGA based feedback controllers. Multiple feedback loops are used to and dynamically tune the magnets. The current implementation and results will be presented. Work on a new spin flipper for RHIC (Relativistic Heavy Ion Collider) incorporating multiple dynamically tuned high-Q AC-dipoles has been developed for RHIC spin-physics experiments. A spin flipper is needed to cancel systematic errors by reversing the spin direction of the two colliding beams multiple times during a store. The spin flipper system consists of four DC-dipole magnets (spin rotators) and five AC-dipole magnets. Multiple AC-dipoles are needed to localize the driven coherent betatron oscillation inside the spin flipper. Operationally the AC-dipoles form two swept frequency bumps that minimize the effect of the AC-dipole dipoles outside of the spin flipper. Both AC bumps operate at the same frequency, but are phase shifted from each other. The AC-dipoles therefore require precise control over amplitude and phase making the implementation of the AC-dipole controller the central challenge.

  3. Field of a helical Siberian Snake

    Energy Technology Data Exchange (ETDEWEB)

    Luccio, A. [Brookhaven National Lab., Upton, NY (United States)

    1995-02-01

    To preserve the spin polarization of a beam of high energy protons in a circular accelerator, magnets with periodic magnetic field, called Siberian Snakes are being used. Recently, it was proposed to build Siberian Snakes with superconducting helical dipoles. In a helical, or twisted dipole, the magnetic field is perpendicular to the axis of the helix and rotates around it as one proceeds along the magnet. In an engineering study of a 4 Tesla helical snake, the coil geometry is derived, by twisting, from the geometry of a cosine superconducting dipole. While waiting for magnetic measurement data on such a prototype, an analytical expression for the field of the helice is important, to calculate the particle trajectories and the spin precession in the helix. This model will also allow to determine the optical characteristics of the snake, as an insertion in the lattice of the accelerator. In particular, one can calculate the integrated multipoles through the magnet and the equivalent transfer matrix. An expression for the field in the helix body, i.e., excluding the fringe field was given in a classical paper. An alternate expression can be found by elaborating on the treatment of the field of a transverse wiggler obtained under the rather general conditions that the variables are separable. This expression exactly satisfies Maxwell`s div and curl equations for a stationary field, {del} {center_dot} B = 0, {del} x B = 0. This approach is useful in that it will allow one to use much of the work already done on the problem of inserting wigglers and undulators in the lattice of a circular accelerator.

  4. Snakes: An Integrated Unit Plan.

    Science.gov (United States)

    Lawrence, Lisa

    This document presents an integrated unit plan on snakes targeting second grade students. Objectives of the unit include developing concepts of living things, understanding the contribution and importance of snakes to the environment, and making connections between different disciplines. The unit integrates the topic of snakes into the areas of…

  5. OVERVIEW AND STATUS OF THE STAR DETECTOR AT RHIC

    International Nuclear Information System (INIS)

    CHRISTIE, W.B.

    1999-01-01

    Presented here is the current status of the STAR Detector. STAR is one of the four detectors being constructed at the RHIC collider facility. The STAR detector is scheduled to have its first engineering run with the RHIC beams about six months from the date of this conference. The STAR project is on schedule and expects to recomplete on time

  6. Water cooling coil

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, S; Ito, Y; Kazawa, Y

    1975-02-05

    Object: To provide a water cooling coil in a toroidal nuclear fusion device, in which coil is formed into a small-size in section so as not to increase dimensions, weight or the like of machineries including the coil. Structure: A conductor arranged as an outermost layer of a multiple-wind water cooling coil comprises a hollow conductor, which is directly cooled by fluid, and as a consequence, a solid conductor disposed interiorly thereof is cooled indirectly.

  7. Addiction to Snake Venom.

    Science.gov (United States)

    Das, Saibal; Barnwal, Preeti; Maiti, Tanay; Ramasamy, Anand; Mondal, Somnath; Babu, Dinesh

    2017-07-03

    The nature of addiction depends on various factors. The tendency to have already used several addictive substances and to seek high sensation experiences as a result of specific personality traits may lead to extreme and peculiar forms of addictions. Even belonging to specific social and cultural background may lead to such forms of addiction such as intentional snake bite and willful envenomation. In this article, we have discussed the peculiarities and practical insight of such addiction to snake venom. The possible molecular mechanism behind such venom-mediated reinforcement has also been highlighted. Finally, we have stressed upon the treatment and de-addiction measures.

  8. Pulmonoscopy of Snakes.

    Science.gov (United States)

    Knotek, Zdenek; Jekl, Vladimir

    2015-09-01

    Pulmonoscopy is a practical diagnostic tool for investigating respiratory diseases in snakes. Two different approaches exist for pulmonoscopy, tracheal and transcutaneous. The access to the proximal or distal lung is limited by the length and diameter of the endoscope when using the tracheal approach. The transcutaneous approach allows direct evaluation of the lung and distal trachea through the air sac. Both of the methods are safe, and specific contraindications for pulmonoscopy in snakes are not known except for any anesthesia contraindication. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. 50 CFR 226.205 - Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River...

    Science.gov (United States)

    2010-10-01

    ... salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. The following areas consisting of the water, waterway bottom, and adjacent riparian zone of...

  10. LEPTON AND PHOTON PHYSICS AT RHIC

    International Nuclear Information System (INIS)

    TANNENBAUM, M.J.

    2003-01-01

    Results on physics at RHIC using outgoing leptons and photons will be presented from Au+Au collisions at nucleon-nucleon c.m. energies √(sNN) = 130 GeV and 200 GeV, and from p-p collisions at √(sNN) = 200 GeV. Introduction and motivation will be presented both from the theoretical and experimental perspectives. Topics include open charm production via single e ± , J/Ψ → e + + e - , μ + + μ - and inclusive photon production

  11. RHIC spin physics: Proceedings. Volume 7

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    This proceedings compiles one-page summaries and five transparencies for each talk, with the intention that the speaker should include a web location for additional information in the summary. Also, email addresses are given with the participant list. The order follows the agenda: gluon, polarimetry, accelerator, W production and quark/antiquark polarization, parity violation searches, transversity, single transverse spin, small angle elastic scattering, and the final talk on ep collisions at RHIC. The authors begin the Proceedings with the full set of transparencies from Bob Jaffe`s colloquium on spin, by popular request.

  12. RHIC spin physics: Proceedings. Volume 7

    International Nuclear Information System (INIS)

    1998-01-01

    This proceedings compiles one-page summaries and five transparencies for each talk, with the intention that the speaker should include a web location for additional information in the summary. Also, email addresses are given with the participant list. The order follows the agenda: gluon, polarimetry, accelerator, W production and quark/antiquark polarization, parity violation searches, transversity, single transverse spin, small angle elastic scattering, and the final talk on ep collisions at RHIC. The authors begin the Proceedings with the full set of transparencies from Bob Jaffe's colloquium on spin, by popular request

  13. Some calculations for the RHIC kicker

    International Nuclear Information System (INIS)

    Claus, J.

    1996-12-01

    This paper starts with a brief discussion of the design of the RHIC injection kicker magnets which calls for longitudinal and capacitive sections of the same order as the aperture, not much larger nor much smaller. This makes accurate analytical prediction of their behavior very difficult. In order to gain at least some qualitative insight of that behavior, the author preformed calculations which are based on the actual dimensions of the kickers but which neglect the end effects of the individual sections. The effects of the sectionalization are therefore exaggerated relative to reality in the results

  14. Electronics for the RHIC PHENIX detector

    International Nuclear Information System (INIS)

    Young, G.R.

    1992-01-01

    The PHENIX detector for RHIC is being designed to measure lepton pairs, direct photons and hadrons emitted in collisions of heavy nuclei at center of mass energies up to 200 GeV/(nucleon-pair). The physics goal is tests of predictions concerning the existence and nature of a deconfined state of strongly-interacting matter. The relatively large final state multiplicities, which reach 1500 charged particles per unit of rapidity, place strong demands on detector segmentation and control of electronics cost and power consumption. An overview of present ideas concerning signal processing and data rates for PHENIX will be presented

  15. FEASIBILITY OF INCREASING THE ENERGY OF RHIC

    International Nuclear Information System (INIS)

    MACKAY, W.W.; JAIN, A.; LUCCIO, A.U.; PILAT, F.; ROSER, T.; TEPIKIAN, S.; TROBOJEVIC, D.

    2001-01-01

    In this paper we discuss the possibility of increasing the energy of beams in RHIC by as much as 30% with a modest trade-off in luminosity. The arc dipoles and quadrupoles were designed with considerable margin. For higher energies (>100 GeV/nucleon) the minimum β* may be required to increase as the interaction region triplets saturate. The separator magnets (DX) have the least margin for increased field, so we consider three scenarios: allowing for a small crossing angle with the present DX magnets, upgrading the DX magnets to higher strength, and permitting a crossing angle of ∼1degree by removing the DX magnets altogether

  16. Heavy flavour production at RHIC and LHC

    Directory of Open Access Journals (Sweden)

    Innocenti Gian Michele

    2018-01-01

    Full Text Available In this proceedings, I present selected experimental results on heavy-flavour production at RHIC and at the LHC, which were presented at the Strangeness in Quark Matter 2017 conference. I will present a brief introduction to the heavy-flavour physics in heavy ion collisions and I will focus on recents measurements of in-medium energy loss and and collective properties of heavy-flavour particles, which provided important information on the mechanisms of heavy flavour interaction with the hot and dense medium created in ultra-relativistic heavy-ion collisions.

  17. TRANSVERSE OPTICS IMPROVEMENTS FOR RHIC RUN 4.

    Energy Technology Data Exchange (ETDEWEB)

    VAN ZEIJTS,J.

    2004-07-05

    The magnetic settings in RHIC are driven by an on-line model, and the quality of the resulting lattice functions depend on the correctness of the settings, and knowledge of the magnet transfer-functions. Here we first present the different inputs into the model, including dipole sextupole components, used to set tunes and chromaticities along the ramp. Based on an analysis of measured tunes along the FY03 polarized proton ramp, we present predictions for quadrupole transfer-function changes which have been implemented for the FY04 Au ramp. We show the improved model agreement for tunes along the ramp, and measured transverse phase-advance at store.

  18. THE RHIC BEAM ABORT KICKER SYSTEM

    International Nuclear Information System (INIS)

    Hahn, H.

    1999-01-01

    THE ENERGY STORED IN THE RHIC BEAM IS ABOUT 200 KJ PER RING AT DESIGN ENERGY AND INTENSITY. TO PREVENT QUENCHING OF THE SUPERCONDUCTING MAGNETS OR MATERIAL DAMAGE, THE BEAM WILL BE SAFELY DISPOSED OF BY AN INTERNAL BEAM ABORT SYSTEM, WHICH INCLUDES THE KICKER MAGNETS, THE PULSED POWER SUPPLIES, AND THE DUMP ABSORBER. DISPOSAL OF HEAVY IONS, SUCH AS GOLD, IMPOSES DESIGN CONSTRAINTS MORE SEVERE THAN THOSE FOR PROTON BEAMS OF EQUAL INTENSITY. IN ORDER TO MINIMIZE THE THERMAL SHOCK IN THE CARBON-FIBER DUMP BLOCK, THE BUNCHES MUST BE LATERALLY DISPERSED

  19. B-physics at RHIC: An opportunity

    International Nuclear Information System (INIS)

    Atiya, M.S.; White, S.; Marx, M.

    1994-01-01

    B physics provides a unique window for investigation and confirmation of our picture of CP violation, as well as an opportunity to explore physics beyond the Standard Model. Because of this richness of physics, programs for the study of the B sector are in progress or under development at most of the major facilities for high energy physics in the world. In this note we suggest that a B program at the RHIC facility at BNL could provide timely and complementary information to our understanding of physics within and beyond the Standard Model

  20. "Upgraded" physics at the LHC and RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Llope, W. J. [Wayne State University, Detroit, MI (United States)

    2017-09-03

    Closeout materials enclosed. This grant supported a postdoctoral scientist (S. Jowzaee) and the tuition for a graduate student (B. Erko), both working under the supervision of Prof. W.J. Llope at Wayne State University. Travel to a STAR Collaboration Meeting and the Quark Matter 2017 conference was also supported. The physics research concentrated on particle-identified two-particle correlations in the Beam Energy Scan data from the STAR experiment at RHIC. S. Jowzaee gave an oral presentation on this research at the Quark Matter 2017 conference.

  1. Recent Results from PHOBOS at Rhic

    Science.gov (United States)

    Garcia, Edmundo; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Busza, W.; Carroll, A.; Chai, Z.; Decowski, M. P.; Garcia, E.; Gburek, T.; George, N.; Gulbrandsen, K.; Halliwell, C.; Hamblen, J.; Hauer, M.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Khan, N.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Reed, C.; Roland, C.; Roland, G.; Sagerer, J.; Seals, H.; Sedykh, I.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tonjes, M. B.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Wenger, E.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wysłouch, B.

    The PHOBOS detector is one of four heavy-ion experiments at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. In this paper we will review some of the results of PHOBOS from the data collected in p+p, d+Au and Au+Au collisions at nucleon-nucleon center-of-mass energies up to 200 GeV. In the most central Au+Au collisions at the highest energy, evidence is found for the formation of a very high energy density and highly interactive system, which can not be described in terms of hadrons, and which has a relatively low baryon density.

  2. NCSX Trim Coil Design

    International Nuclear Information System (INIS)

    Kalish, M.; Brooks, A.; Rushinski, J.; Upcavage, R.

    2009-01-01

    The National Compact Stellarator Experiment (NCSX) was being constructed at the Princeton Plasma Physics Laboratory in partnership with Oak Ridge National Laboratory before work was stopped in 2008. The objective of this experiment was to develop the stellarator concept and evaluate it's potential as a model for future fusion power plants. Stellarator design requires very precisely positioned Modular Coils of complex shape to form 3D plasmas. In the design of NCSX, Trim Coils were required to compensate for both the positioning of the coils during assembly and the fabrication tolerances of the Modular Coils. Use of the Trim Coils allowed for larger tolerances increasing ease of assembly and decreasing overall cost. A set of Trim coils was developed to suppress the toroidal flux in island regions due to misalignment, magnetic materials, and eddy currents. The requirement imposed upon the design forced the toroidal flux in island regions below 10% of the total toroidal flux in the plasma. An analysis was first performed to evaluate candidate Trim Coil configurations iterating both the size, number, and position of the coils. The design was optimized considering both performance and cost while staying within the tight restraints presented by the space limited geometry. The final design of the Trim Coils incorporated a 48 Coil top bottom symmetric set. Fabrication costs were minimized by having only two coil types and using a planar conventional design with off the shelf commercial conductor. The Trim Coil design incorporated supports made from simple structural shapes assembled together in a way which allowed for adjustment as well as accommodation for the tolerance build up on the mating surfaces. This paper will summarize the analysis that led to the optimization of the Trim Coils set, the trim coil mechanical design, thermal and stress analysis, and the design of the supporting Trim Coil structure

  3. Dual coil ignition system

    Energy Technology Data Exchange (ETDEWEB)

    Huberts, Garlan J.; Qu, Qiuping; Czekala, Michael Damian

    2017-03-28

    A dual coil ignition system is provided. The dual coil ignition system includes a first inductive ignition coil including a first primary winding and a first secondary winding, and a second inductive ignition coil including a second primary winding and a second secondary winding, the second secondary winding connected in series to the first secondary winding. The dual coil ignition system further includes a diode network including a first diode and a second diode connected between the first secondary winding and the second secondary winding.

  4. Proceedings of the third workshop on experiments and detectors for a relativistic heavy ion collider (RHIC)

    International Nuclear Information System (INIS)

    Shivakumar, B.; Vincent, P.

    1988-01-01

    This report contains papers on the following topics: the RHIC Project; summary of the working group on calorimetry; J//Psi/ measurements in heavy ion collisions at CERN; QCD jets at RHIC; tracking and particle identification; a 4π tracking spectrometer for RHIC; Bose-Einstein measurements at RHIC in light of new data; summary of working group on read-out electronics; data acquisition for RHIC; summary of the working group on detector simulation; B-physics at RHIC; and CP violation revisited at BNL, B-physics at RHIC

  5. Snow snake performance monitoring.

    Science.gov (United States)

    2008-12-01

    A recent study, Three-Dimensional Roughness Elements for Snow Retention (FHWA-WY-06/04F) (Tabler 2006), demonstrated : positive evidence for the effectiveness of Snow Snakes, a new type of snow fence suitable for use within the highway right-of...

  6. Where Galactic Snakes Live

    Science.gov (United States)

    2006-01-01

    This infrared image from NASA's Spitzer Space Telescope shows what astronomers are referring to as a 'snake' (upper left) and its surrounding stormy environment. The sinuous object is actually the core of a thick, sooty cloud large enough to swallow dozens of solar systems. In fact, astronomers say the 'snake's belly' may be harboring beastly stars in the process of forming. The galactic creepy crawler to the right of the snake is another thick cloud core, in which additional burgeoning massive stars might be lurking. The colorful regions below the two cloud cores are less dense cloud material, in which dust has been heated by starlight and glows with infrared light. Yellow and orange dots throughout the image are monstrous developing stars; the red star on the 'belly' of the snake is 20 to 50 times as massive as our sun. The blue dots are foreground stars. The red ball at the bottom left is a 'supernova remnant,' the remains of massive star that died in a fiery blast. Astronomers speculate that radiation and winds from the star before it died, in addition to a shock wave created when it exploded, might have played a role in creating the snake. Spitzer was able to spot the two black cloud cores using its heat-seeking infrared vision. The objects are hiding in the dusty plane of our Milky Way galaxy, invisible to optical telescopes. Because their heat, or infrared light, can sneak through the dust, they first showed up in infrared images from past missions. The cloud cores are so thick with dust that if you were to somehow transport yourself into the middle of them, you would see nothing but black, not even a star in the sky. Now, that's spooky! Spitzer's new view of the region provides the best look yet at the massive embryonic stars hiding inside the snake. Astronomers say these observations will ultimately help them better understand how massive stars form. By studying the clustering and range of masses of the stellar embryos, they hope to determine if the stars

  7. Current status of PHOBOS at sign RHIC

    International Nuclear Information System (INIS)

    Betts, R.R.; Univ. of Illinois, Chicago, IL

    1996-01-01

    Four experiments are currently approved for the first measurements with colliding heavy ion beams from the Relativistic Heavy Ion Collider (RHIC) which is scheduled to come into operation in Spring 1999. These experiments are named STAR, Phoenix, PHOBOS and Brahms. It is expected that central collisions of 100 GeV/u Au + Au at RHIC will lead to energy densities far above any so far attained in the laboratory and it is suspected and hoped that this situation will lead to qualitatively new physics perhaps associated with the creation of a large volume containing a plasma of deconfined quarks and gluons. All four experiments attempt to search for signatures of new physics through combinations of measurements of quantities such as the multiplicity of produced particles, the average transverse momentum of these particles, fluctuations in their multiplicity distribution, their flavor composition, the size scales of the volume from which they are emitted, mass shifts and changes in the decay widths of resonances which decay inside the high energy density volume etc. The PHOBOS detector addresses these issues with a Multiplicity Array which covers the pseudo-rapidity region -5.3 ≤ η ≤ 5.3 with a coverage of 85% of 4π and also incorporates a Vertex Detector. The Multiplicity Array is complemented by two Multi-Particle Spectrometers, each of which cover the range 0.5 ≤ η ≤ 1.5 and azimuthal angle range Δφ = 11 degree. Various trigger and monitor detectors complete PHOBOS

  8. First results from RHIC-PHENIX

    CERN Document Server

    Ghosh, T K; Adler, S S; Ajitanand, N N; Akiba, Y; Alexander, J; Aphecetche, L; Arai, Y; Aronson, S H; Averbeck, R; Awes, T C; Barish, K N; Barnes, P D; Barrette, J; Bassalleck, B; Bathe, S; Baublis, V; Bazilevsky, A; Belikov, S V; Bellaiche, F G; Belyaev, S T; Bennett, M J; Berdnikov, Yu A; Botelho, S S; Brooks, M L; Brown, D S; Bruner, N L; Bucher, D; Büsching, H; Bunce, G M; Burward-Hoy, J M; Butsyk, S; Carey, T A; Chand, P; Chang, J; Chang, W C; Chavez, L L; Chernichenko, S K; Chi, C Y; Chiba, J; Chiu, M; Choudhury, R K; Christ, T; Chujo, T; Chung, M S; Chung, P; Cianciolo, V; Cole, B A; D'Enterria, D G; Dávid, G; Delagrange, H; Denisov, A; Deshpande, A A; Desmond, E J; Dietzsch, O; Dinesh, B V; Drees, A; Durum, A A; Dutta, D; Ebisu, K; Efremenko, Yu V; Chenawi, K E; En-Yo, H; Esumi, S C; Ewell, L A; Ferdousi, T; Fields, D E; Fokin, S L; Fraenkel, Zeev; Franz, A; Frawley, A D; Fung, S Y; Garpman, S; Ghosh, T K; Glenn, A; Godoi, A L; Goto, Y; Greene, S V; Grosse-Perdekamp, M; Gupta, S K; Guryn, W; Gustafsson, Hans Åke; Haggerty, J S; Hamagaki, H; Hansen, A G; Hara, H; Hartouni, E P; Havano, R; Hayashi, N; He, X; Hemmick, T K; Heuser, J M; Hill, J C; Ho, D S; Homma, K; Hong, B; Hoover, A; Ichihara, T; Imai, K; Ippolitov, M S; Ishihara, M; Jacak, B V; Jang, W Y; Jia, J; Johnson, B M; Johnson, S C; Joo, K S; Kametani, S; Kang, J H; Kann, M; Kapoor, S S; Kelly, S; Khachaturov, B A; Khanzadeev, A V; Kikuchi, J; Kim, D J; Kim, H J; Kim, S Y; Kim, Y G; Kinnison, W W; Kistenev, E P; Kiyomichi, A; Klein-Bösing, C; Klinksiek, S A; Kochenda, L M; Kochetkov, D; Kochetkov, V; Köhler, D; Kohama, T; Kozlov, A; Kroon, P J; Kurita, K; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R A; Lajoie, J G; Lauret, J; Lebedev, A; Lee, D M; Leitch, M J; Li, X H; Li, Z; Lim, D J; Liu, M X; Liu, X; Liu, Z; Maguire, C F; Mahon, J; Makdisi, Y I; Man'ko, V I; Mao, Y; Mark, S K; Markacs, S; Martínez, G; Marx, M D; Massaike, A; Matathias, F; Matsumoto, T; McGaughey, P L; Melnikov, E A; Merschmeyer, M; Messer, F; Messer, M; Miake, Y; Miller, T E; Milov, A; Mioduszewski, S; Mischke, R E; Mishra, G C; Mitchell, J T; Mohanty, A K; Morrison, D P; Moss, J M; Muhlbacher, F; Muniruzzaman, M; Murata, J; Nagamiya, S; Nagasaka, Y; Nagle, J L; Nakada, Y; Nandi, B K; Newby, J; Nikkinen, L; Nilsson, P O; Nishimura, S; Nyanin, A S; Nystrand, J; O'Brien, E; Ogilvie, C A; Ohnishi, H; Ojha, I D; Ono, M; Onuchin, V A; Oskarsson, A; Österman, L; Otterlund, I; Oyama, K; Paffrath, L; Palounek, A P T; Pantuev, V S; Papavassiliou, V; Pate, S F; Peitzmann, Thomas; Petridis, A N; Pinkenburg, C H; Pisani, R P; Pitukhin, P; Plasil, F; Pollack, M E; Pope, K; Purschke, M L; Ravinovich, I; Read, K F; Reygers, K; Riabov, V; Riabov, Y; Rosati, M; Rose, A A; Ryu, S S; Saitô, N; Sakaguchi, A; Sakaguchi, T; Sako, H; Sakuma, T; Samsonov, V; Sangster, T C; Santo, R; Sato, H D; Sato, S; Sawada, S; Schlei, B R; Schutz, Y; Semenov, V; Seto, R; Shea, T K; Shein, I; Shibata, T A; Shigaki, K; Shiina, T; Shin, Y H; Sibiryak, Yu; Silvermyr, D; Sim, K S; Simon-Gillo, J; Singh, C P; Singh, V; Sivertz, M; Soldatov, A; Soltz, R A; Sørensen, S; Stankus, P W; Starinsky, N; Steinberg, P; Stenlund, E; Ster, A; Stoll, S P; Sugioka, M; Sugitate, T; Sullivan, J P; Sumi, Y; Sun, Z; Suzuki, M; Takagui, E M; Taketani, A; Tamai, M; Tanaka, Y; Taniguchi, E; Tannenbaum, M J; Thomas, J; Thomas, J H; Thomas, T L; Tian, W; Tojo, J; Torii, H A; Towell, R S; Tserruya, Itzhak; Tsuruoke, H; Tsvetkov, A A; Tuli, S K; Tydesjo, H; Tyurin, N; Ushiroda, T; van Hecke, H; Velissaris, C; Velkovska, J; Velkovsky, M; Vingradov, A A; Volkov, M A; Vorobyov, A A; Vznuzdaev, E A; Wang, H; Watanabe, Y; White, S N; Witzig, C; Wohn, F K; Woody, C L; Xie, W; Yagi, K; Yokkaichi, S; Young, G R; Yushmanov, I E; Zajc, W A; Zhang, Z; Zhou, S

    2001-01-01

    The PHENIX experiment consists of a large detector system located at the newly commissioned Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory. The primary goal of the PHENIX experiment is to look for signatures of the QCD prediction of a deconfined high-energy-density phase of nuclear matter and the quark gluon plasma. PHENIX started taking data for Au+Au collisions at square root (s/sub NN/)=130 GeV in June 2000. The signals from the beam-beam counter (BBC) and zero degree calorimeter (ZDC) are used to determine the centrality of the collision. A Glauber model reproduces the ZDC spectrum reasonably well to determine the participants in a collision. The charged particle multiplicity distribution from the first PHENIX paper is compared with the other RHIC experiment and the CERN and SPS results. Transverse momentum of photons are measured in the electro-magnetic calorimeter (EMCal) and preliminary results an presented. Particle identification is made by a time-of-flight (TOF) detecto...

  9. CONTINUOUS ABORT GAP CLEANING AT RHIC

    International Nuclear Information System (INIS)

    DREES, A.; FLILLER, R.III.; FU, W.; MICHNOFF, R.

    2004-01-01

    Since the RHIC Au-Au run in the year 2001 the 200 MHz cavity system was used at storage and a 28 MHz system during injection and acceleration. The rebucketing procedure potentially causes a higher debunching rate of heavy ion beams in addition to amplifying debunching due to other mechanisms. At the end of a four hour store, debunched beam can easily account for more than 50% of the total beam intensity. This effect is even stronger with the achieved high intensities of the RHIC Au-Au run in 2004. A beam abort at the presence of a lot of debunched beam bears the risk of magnet quenching and experimental detector damage due to uncontrolled beam losses. Thus it is desirable to avoid any accumulation of debunched beam from the beginning of each store, in particular to anticipate cases of unscheduled beam aborts due to a system failure. A combination of a fast transverse kickers and the new 2-stage copper collimator system are used to clean the abort gap continuously throughout the store with a repetition rate of 1 Hz. This report gives. an overview of the new gap cleaning procedure and the achieved performance

  10. UP-GRADED RHIC INJECTION SYSTEM.

    Energy Technology Data Exchange (ETDEWEB)

    HAHN,H.FISCHER,W.SEMERTZIDIS,Y.K.WARBURTON,D.S.

    2003-05-12

    The design of the RHIC injection systems anticipated the possibility of filling and operating the rings with a 120 bunch pattern, corresponding to 110 bunches after allowing for the abort gap. Beam measurements during the 2002 run confirmed the possibility, although at the expense of severe transverse emittance growth and thus not on an operational basis. An improvement program was initiated with the goal of reducing the kicker rise time from 110 to {approx}95 ns and of minimizing pulse timing jitter and drift. The major components of the injection system are 4 kicker magnets and Blmlein pulsers using thyratron switches. The kicker terminating resistor and operating voltage was increased to reduce the rise time. Timing has been stabilized by using commercial trigger units and extremely stable dc supplies for the thyratron reservoir. A fiber optical connection between control room and the thyratron trigger unit has been provided, thereby allowing the operator to adjust timing individually for each kicker unit. The changes were successfully implemented for use in the RHIC operation.

  11. The PHOBOS perspective on discoveries at RHIC

    Science.gov (United States)

    Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Becker, B.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Chai, Z.; Decowski, M. P.; García, E.; Gburek, T.; George, N. K.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Harrington, A. S.; Hauer, M.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lee, J. W.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Seals, H.; Sedykh, I.; Skulski, W.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tang, J.-L.; Tonjes, M. B.; Trzupek, A.; Vale, C. M.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Wenger, E.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.; Zhang, J.; Phobos Collaboration

    2005-08-01

    This paper describes the conclusions that can be drawn from the data taken thus far with the PHOBOS detector at RHIC. In the most central Au + Au collisions at the highest beam energy, evidence is found for the formation of a very high energy density system whose description in terms of simple hadronic degrees of freedom is inappropriate. Furthermore, the constituents of this novel system are found to undergo a significant level of interaction. The properties of particle production at RHIC energies are shown to follow a number of simple scaling behaviors, some of which continue trends found at lower energies or in simpler systems. As a function of centrality, the total number of charged particles scales with the number of participating nucleons. When comparing Au + Au at different centralities, the dependence of the yield on the number of participants at higher p ( ˜4 GeV/c) is very similar to that at low transverse momentum. The measured values of charged particle pseudorapidity density and elliptic flow were found to be independent of energy over a broad range of pseudorapidities when effectively viewed in the rest frame of one of the colliding nuclei, a property we describe as "extended longitudinal scaling". Finally, the centrality and energy dependences of several observables were found to factorize to a surprising degree.

  12. A Prototype Ionization Profile Monitor for RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Connolly, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Cameron, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ryan, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Shea, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sikora, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    1997-03-17

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Lab will accelerate and store beams of ions ranging from protons to gold nuclei. Transverse beam profiles will be obtained by measuring the distribution of free electrons formed by beam ionization of the residual gas. The electrons are swept from the beamline by a transverse electric field, amplified by a microchannel plate (MCP), and collected on a circuit board with strip anodes oriented parallel to the beam axis. A uniform magnetic field,parallel to the sweep electric field, counters the defocusing effects of space charge and recoil momentum. A single-plane prototype ionization profile montor (IPM) was installed near the end of the AGS-to-RHIC transfer line (ATR) and tested during the sextant commissioning rung. It measured vertical profiles of single bunches of Au nuclei with intensities of 0.6-1.0 x 108 particles. These profiles are compared to profiles on a fluorescent screen (WF3) located 2m downstream from the IPM. This paper describes the detector and gives results from the beam test.

  13. Biomaterials Made from Coiled-Coil Peptides.

    Science.gov (United States)

    Conticello, Vincent; Hughes, Spencer; Modlin, Charles

    The development of biomaterials designed for specific applications is an important objective in personalized medicine. While the breadth and prominence of biomaterials have increased exponentially over the past decades, critical challenges remain to be addressed, particularly in the development of biomaterials that exhibit highly specific functions. These functional properties are often encoded within the molecular structure of the component molecules. Proteins, as a consequence of their structural specificity, represent useful substrates for the construction of functional biomaterials through rational design. This chapter provides an in-depth survey of biomaterials constructed from coiled-coils, one of the best-understood protein structural motifs. We discuss the utility of this structurally diverse and functionally tunable class of proteins for the creation of novel biomaterials. This discussion illustrates the progress that has been made in the development of coiled-coil biomaterials by showcasing studies that bridge the gap between the academic science and potential technological impact.

  14. High luminosity electron-hadron collider eRHIC

    Energy Technology Data Exchange (ETDEWEB)

    Ptitsyn, V.; Aschenauer, E.; Bai, M.; Beebe-Wang, J.; Belomestnykh, S.; Ben-Zvi, I.; Blaskiewicz, M..; Calaga, R.; Chang, X.; Fedotov, A.; Gassner, D.; Hammons, L.; Hahn, H.; Hammons, L.; He, P.; Hao, Y.; Jackson, W.; Jain, A.; Johnson, E.C.; Kayran, D.; Kewisch, J.; Litvinenko, V.N.; Luo, Y.; Mahler, G.; McIntyre, G.; Meng, W.; Minty, M.; Parker, B.; Pikin, A.; Rao, T.; Roser, T.; Skaritka, J.; Sheehy, B.; Skaritka, J.; Tepikian, S.; Than, Y.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Wang, G.; Webb, S.; Wu, Q.; Xu, W.; Pozdeyev, E.; Tsentalovich, E.

    2011-03-28

    We present the design of a future high-energy high-luminosity electron-hadron collider at RHIC called eRHIC. We plan on adding 20 (potentially 30) GeV energy recovery linacs to accelerate and to collide polarized and unpolarized electrons with hadrons in RHIC. The center-of-mass energy of eRHIC will range from 30 to 200 GeV. The luminosity exceeding 10{sup 34} cm{sup -2} s{sup -1} can be achieved in eRHIC using the low-beta interaction region with a 10 mrad crab crossing. We report on the progress of important eRHIC R&D such as the high-current polarized electron source, the coherent electron cooling, ERL test facility and the compact magnets for recirculation passes. A natural staging scenario of step-by-step increases of the electron beam energy by building-up of eRHIC's SRF linacs is presented.

  15. Snake antivenom for snake venom induced consumption coagulopathy

    OpenAIRE

    Maduwage, Kalana; Buckley, Nick A.; Janaka de Silva, H.; Lalloo, David; Isbister, Geoffrey K.

    2015-01-01

    Background\\ud \\ud Snake venom induced consumption coagulopathy is a major systemic effect of envenoming. Observational studies suggest that antivenom improves outcomes for venom induced consumption coagulopathy in some snakebites and not others. However, the effectiveness of snake antivenom in all cases of venom induced consumption coagulopathy is controversial.\\ud \\ud Objectives\\ud \\ud To assess the effect of snake antivenom as a treatment for venom induced consumption coagulopathy in people...

  16. Analysis, reconstruction and manipulation using arterial snakes

    KAUST Repository

    Li, Guo

    2010-01-01

    Man-made objects often consist of detailed and interleaving structures, which are created using cane, coils, metal wires, rods, etc. The delicate structures, although manufactured using simple procedures, are challenging to scan and reconstruct. We observe that such structures are inherently 1D, and hence are naturally represented using an arrangement of generating curves. We refer to the resultant surfaces as arterial surfaces. In this paper we approach for analyzing, reconstructing, and manipulating such arterial surfaces. The core of the algorithm is a novel deformable model, called arterial snake, that simultaneously captures the topology and geometry of the arterial objects. The recovered snakes produce a natural decomposition of the raw scans, with the decomposed parts often capturing meaningful object sections. We demonstrate the robustness of our algorithm on a variety of arterial objects corrupted with noise, outliers, and with large parts missing. We present a range of applications including reconstruction, topology repairing, and manipulation of arterial surfaces by directly controlling the underlying curve network and the associated sectional profiles, which are otherwise challenging to perform. © 2010 ACM.

  17. Critical examination of RHIC paradigms - mostly high pT

    International Nuclear Information System (INIS)

    Tannenbaum, M.I.

    2009-01-01

    A critical examination of RHIC paradigms is presented. Topics include: search for a critical point with a low energy scan; the lack of understanding of radiative processes in a medium in QCD compared in detail to examples from QED; the reason why some physicists started to measure particles at large p T in the 1960's; a review of the discovery of hard-scattering in p-p collisions in the 1970's via single-inclusive and two-particle correlations and application of these techniques at RHIC. Several paradigms in both soft and hard physics which are popular at RHIC are discussed and challenged.

  18. Modeling RHIC using the standard machine formal accelerator description

    International Nuclear Information System (INIS)

    Pilat, F.; Trahern, C.G.; Wei, J.

    1997-01-01

    The Standard Machine Format (SMF) is a structured description of accelerator lattices which supports both the hierarchy of beam lines and generic lattice objects as well as those deviations (field errors, alignment efforts, etc.) associated with each component of the as-installed machine. In this paper we discuss the use of SMF to describe the Relativistic Heavy Ion Collider (RHIC) as well as the ancillary data structures (such as field quality measurements) that are necessarily incorporated into the RHIC SMF model. Future applications of SMF are outlined, including its use in the RHIC operational environment

  19. Hypernucleus Production at RHIC and HIRFL-CSR Energy

    International Nuclear Information System (INIS)

    Zhang, S.; Xu, Z.; Chen, J.H.; Ma, Y.G.; Tang, Z.B.

    2010-01-01

    We calculated the hypertriton production at RHIC-STAR and HIRFL-CSR acceptance, with a multi-phase transport model (AMPT) and a relativistic transport model (ART), respectively. In specific, we calculated the Strangeness Population Factor S 3 = Λ 3 H/( 3 H e x Λ/p) at different beam energy. Our results from AGS to RHIC energy indicated that the collision system may change from hadronic phase at AGS energies to partonic phase at RHIC energies. Our calculation at HIRFL-CSR energy supports the proposal to measure hypertriton at HIRFL-CSR.

  20. Responses by king snakes (Lampropeltis getulus) to chemicals from colubrid and crotaline snakes.

    Science.gov (United States)

    Weldon, P J; Schell, F M

    1984-10-01

    Four litters of king snakes (Lampropeltis getulus), a snake-eating species, were tested for responses to chemicals from colubrid and crotaline snakes. King snakes presented with swabs rubbed against the dorsal skin of living snakes and with swabs treated with methylene chloride extracts of shed snake skins tongue-flicked more to swabs from a northern copperhead (Agkistrodon contortrix), a crotaline, than to swabs from some colubrid snakes or to blank swabs. Six out of 10 king snakes in one litter attacked and attempted to ingest swabs treated with snake skin chemicals, implicating these chemicals as feeding stimuli for these ophiophagous snakes. Ingestively naive king snakes presented with plain air and snake odors in an olfactometer tongue-flicked more to snake odors. This study and others suggest that crotaline and colubrid snakes can be distinguished by chemical cues.

  1. Superconducting magnetic coil

    Science.gov (United States)

    Aized, Dawood; Schwall, Robert E.

    1996-06-11

    A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

  2. First turn around strategy for RHIC

    International Nuclear Information System (INIS)

    Milutinovic, J.; Ruggiero, A.G.

    1991-06-01

    We present a strategy for achieving the so-called first turn around in RHIC. The strategy is based on the same method we had proposed to correct a distorted closed orbit in RHIC, i.e., on a generalization of the local three-bump method. We found out that the method is very effective in passing the beam through a non-ideal, insufficiently known, machine. We tested that software on ten different Gaussian distributions of dominant orbit distorting lattice imperfections. The perturbed lattice was generated by the code PATRIS, which was also adapted to control the newly developed software. In all of the ten distributions the software was capable of passing the beam through in 2--3 injection attempts, at full sextupole strength. It was also determined that once the beam makes the first turn around and all the correctors are energized, it stays in the machine for at least several hundred turns that we had checked. The quality of the orbit, that was established in this way, was also found to be very good, i.e., the residual distortions at the places of large beta function were much less than one millimeter. With one or two monitors/correctors broken, the software established a first turn around without any extra difficulties. The quality of such orbit was, of course, somewhat degraded, especially around the broken devices. It was also observed that, in the process of actual closing, the beam develops free betatron oscillations in the amplitude range of 1--5 mm, which can be reduced either by changing the injection conditions to better match the actual closed orbit or by an appropriate damping device. The hardware proposed for RHIC is more than sufficient to meet the demands of the first turn controlling software. The maximum kick angle to be applied to the beam would require less than 2/3 of the corrector's top strength even at the top magnetic rigidity Bρ = 850 T·m, which means that the correctors will be performing an easy task at injection

  3. Cooling and dehumidifying coils

    International Nuclear Information System (INIS)

    Murthy, M.V.K.

    1988-01-01

    The operating features of cooling and dehumidifying coils and their constructional details are discussed. The heat transfer relations as applicable to the boiling refrigerant and a single phase fluid are presented. Methods of accounting for the effect of moisture condensation on the air side heat transfer coefficient and the fin effectiveness are explained. The logic flow necessary to analyze direct expansion coils and chilled water coils is discussed

  4. The JET divertor coil

    International Nuclear Information System (INIS)

    Last, J.R.; Froger, C.; Sborchia, C.

    1989-01-01

    The divertor coil is mounted inside the Jet vacuum vessel and is able to carry 1 MA turns. It is of conventional construction - water cooled copper, epoxy glass insulation -and is contained in a thin stainless steel case. The coil has to be assembled, insulated and encased inside the Jet vacuum vessel. A description of the coil is given, together with technical information (including mechanical effects on the vacuum vessel), an outline of the manufacture process and a time schedule. (author)

  5. Snake studies on Tore Supra

    International Nuclear Information System (INIS)

    Cristofani, P.; Desgranges, C.; Garbet, X.; Geraud, A.; Gil, C.; Hoang, G.T.; Joffrin, E.; Pecquet, A.L.

    1995-01-01

    Snakes have been achieved after pellet injection in Tore Supra during ohmic as well as ICRH discharges as it has already been observed in other machines. On Tore Supra, high speed H 2 pellets were injected into D 2 plasmas under the specified experimental conditions, the matter is deposited in the centre and snakes are produced in 50% of the cases, but they are created on a second much more internal q=1 surface leading probably to a non monotonic current profile. The properties of the snake, induced current modification and the important role of the bootstrap current in the snake formation are described. (K.A.) 5 refs.; 7 figs

  6. Snake Venom Metalloproteinases

    Directory of Open Access Journals (Sweden)

    Gâz Florea Şerban Andrei

    2016-03-01

    Full Text Available As more data are generated from proteome and transcriptome analysis revealing that metalloproteinases represent most of the Viperid and Colubrid venom components authors decided to describe in a short review a classification and some of the multiple activities of snake venom metalloproteinases. SVMPs are classified in three major classes (P-I, P-II and P-III classes based on the presence of various domain structures and according to their domain organization. Furthermore, P-II and P-III classes were separated in subclasses based on distinctive post-translational modifications. SVMPs are synthesized in a latent form, being activated through a Cys-switch mechanism similar to matrix metalloproteinases. Most of the metalloproteinases of the snake venom are responsible for the hemorrhagic events but also have fibrinogenolytic activity, poses apoptotic activity, activate blood coagulation factor II and X, inhibit platelet aggregation, demonstrating that SVMPs have multiple functions in addition to well-known hemorrhagic function.

  7. Physics at Relativistic Heavy Ion Collider (RHIC)

    International Nuclear Information System (INIS)

    Shuryak, E.V.

    1990-08-01

    This introductory talk contains a brief discussion of future experiments at RHIC related to physics of superdense matter. In particular, we consider the relation between space-time picture of the collision and spectra of the observed secondaries. We discuss where one should look for QGP signals and for possible manifestation of the phase transition. We pay more attention to a rather new topic: hadron modification in the gas phase, which is interesting by itself as a collective phenomenon, and also as a precursor indicating what happens with hadrons near the phase transition. We briefly review current understanding of the photon physics, dilepton production, charm and strangeness and J/ψ suppression. At the end we try to classify all possible experiments. 47 refs., 3 figs

  8. Code generation of RHIC accelerator device objects

    International Nuclear Information System (INIS)

    Olsen, R.H.; Hoff, L.; Clifford, T.

    1995-01-01

    A RHIC Accelerator Device Object is an abstraction which provides a software view of a collection of collider control points known as parameters. A grammar has been defined which allows these parameters, along with code describing methods for acquiring and modifying them, to be specified efficiently in compact definition files. These definition files are processed to produce C++ source code. This source code is compiled to produce an object file which can be loaded into a front end computer. Each loaded object serves as an Accelerator Device Object class definition. The collider will be controlled by applications which set and get the parameters in instances of these classes using a suite of interface routines. Significant features of the grammar are described with details about the generated C++ code

  9. Inconsistencies in Models for RHIC and LHC

    CERN Document Server

    Werner, K; Ostapchenko, S; Pierog, T

    2002-01-01

    The interpretation of experimental results at RHIC and in the future also at LHC requires very reliable and realistic models. Considerable effort has been devoted to the development of such models during the past decade, many of them being heavily used in order to analyze data. It is the purpose of this paper to point out serious inconsistencies in the above-mentioned approaches. We will demonstrate that requiring theoretical self-consistency reduces the freedom in modeling high energy nuclear scattering enormously. We will introduce a fully self-consistent formulation of the multiple-scattering scheme in the framework of a Gribov-Regge type effective theory. In addition, we develop new computational techniques which allow for the first time a satisfactory solution of the problem in the sense that calculations of observable quantities can be done strictly within a self-consistent formalism.

  10. Hadron spectroscopy and B physics at RHIC

    International Nuclear Information System (INIS)

    Chung, S.U.; Weygand, D.P.; Willutzki, H.J.

    1991-11-01

    A description is given of the physics opportunities at RHIC regarding quark-gluon spectroscopy. The basic idea is to isolate with appropriate triggers the sub-processes pomeron + pomeron → hadrons and γ * + γ * → hadrons with the net effective mass of hadrons in the range of 1.0 to 10.0 GeV, in order to study the hadronic states composed of quarks and gluons. The double-pomeron interactions are expected to produce glueballs and hybrids preferentially, while the two-offshell-photon initial states should couple predominantly to quarkonia and multiquark states. Of particular interest is the possibility of carrying out a CP-violation study in the self-tagging B decays, B d 0 → K + π - and bar B d 0 → K - π + . 20 refs., 4 figs

  11. MEASUREMENT OF TRANSVERSE ECHOES IN RHIC

    International Nuclear Information System (INIS)

    FISCHER, W.; SATOGATA, T.; TOMAS, R.

    2005-01-01

    Beam echoes are a very sensitive method to measure diffusion, and longitudinal echo measurements were performed in a number of machines. In RHIC, for the first time, a transverse beam echo was observed after applying a dipole kick followed by a quadrupole .kick. After application of the dipole kick, the dipole moment decohered completely due to lattice nonlinearities. When a quadrupole kick is applied at time τ after the dipole kick, the beam re-cohered at time 2τ thus showing an echo response. We describe the experimental setup and measurement results. In the measurements the dipole and quadrupole kick amplitudes, amplitude dependent tune shift, and the time between dipole and quadrupole kick were varied. In addition, measurements were taken with gold bunches of different intensities. These should exhibit different transverse diffusion rates due to intra-beam scattering

  12. COUPLING MEASUREMENT AND CORRECTION AT RHIC

    International Nuclear Information System (INIS)

    PILAT, F.; BEEBE-WANG, J.; FISCHER, W.; PTITSYN, V.; SATOGATA, T.

    2002-01-01

    Coupling correction at RHIC has been operationally achieved through a two-step process: using local triplet skew quadrupoles to compensate coupling corn rolled low-beta triplet quadrupoles, and minimizing the tune separation and residual coupling with orthogonal global skew quadrupole families. An application has been developed for global correction that allows skew quadrupole tuning and tune display with a choice of different tune measurement techniques, including tune-meter, Schottky and phase lock loop (PLL). Coupling effects have been analyzed by using 1024-turn (TBT) information from the beam position monitor (BPM) system. These data allow the reconstruction of the off-diagonal terms of the transfer matrix, a measure of global coupling. At both injection and storage energies, coordination of tune meter kicks with TBT acquisition at 322 BPW's in each ring allows the measurement of local coupling at all BPM locations

  13. Wiggler as spin rotators for RHIC

    International Nuclear Information System (INIS)

    Luccio, A.; Conte, M.

    1993-01-01

    The spin of a polarized particle in a circular accelerator can be rotated with an arrangement of dipoles with field mutually perpendicular and perpendicular to the orbit. To achieve spin rotation, a given field integral value is required. The device must be designed in a way that the particle orbit is distorted as little as possible. It is shown that wigglers with many periods are suitable to achieve spin rotation with minimum orbit distortions. Wigglers are also more compact than more established structures and will use less electric power. Additional advantages include their use for non distructive beam diagnostics. Results are given for the Relativistic Heavy Ion Collider (RHIC) in the polarized proton mode

  14. Conceptual Design of the RHIC Dump Core

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, A. J. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    1995-09-26

    Conceptually, the internal dump consists of a "core" whose purpose is to absorb the energy of the beam, and surrounding shielding whose purpose is to attenuate radiation. Design of the core for an internal dump has two problems which must be overcome. The first problem is preserving the integrity of the dump core. The bunches must be dispersed laterally an amount sufficient to keep the energy density from cracking the dump core material. Since the dump kickers in RHIC are only ~25m upstream of the entrance face of the dump, this is i a difficult problem. The second problem, not addressed in this note, is that dumping the beam should not quench downstream magnets. Preliminary calculations related to both of these problems have been presented in earlier notes.

  15. Note on polarized RHIC bunch arrangement

    International Nuclear Information System (INIS)

    Underwood, D.

    1996-01-01

    We discuss what combinations of bunch polarization in the two RHIC rings are necessary to do the physics measurements at various interaction regions. We also consider the bunches for both the pion inclusive and p-p elastic polarization measurements. Important factors to consider are the direction of the polarization with respect to the momentum in each bunch, the beam gas backgrounds, and the simulation of zero - polarization in one beam by averaging + and - helicity, and luminosity monitoring for normalization. These considerations can be addressed by setting the relative number of each of the 9 combinations possible at each of the 6 interaction regions. The combinations are (+ empty -) yellow X (+ empty -)blue, where yellow and blue are the counter-rotating rings

  16. RHIC 10 Hz global orbit feedback system

    International Nuclear Information System (INIS)

    Michnoff, R.; Arnold, L.; Carboni, L.; Cerniglia, P.; Curcio, A.; DeSanto, L.; Folz, C.; Ho, C.; Hoff, L.; Hulsart, R.; Karl, R.; Luo, Y.; Liu, C.; MacKay, W.; Mahler, G.; Meng, W.; Mernick, K.; Minty, M.; Montag, C.; Olsen, R.; Piacentino, J.; Popken, P.; Przybylinski, R.; Ptitsyn, V.; Ritter, J.; Schoenfeld, R.; Thieberger, P.; Tuozzolo, J.; Weston, A.; White, J.; Ziminski, P.; Zimmerman, P.

    2011-01-01

    Vibrations of the cryogenic triplet magnets at the Relativistic Heavy Ion Collider (RHIC) are suspected to be causing the horizontal beam perturbations observed at frequencies around 10 Hz. Several solutions to counteract the effect have been considered in the past, including a local beam feedback system at each of the two experimental areas, reinforcing the magnet base support assembly, and a mechanical servo feedback system. However, the local feedback system was insufficient because perturbation amplitudes outside the experimental areas were still problematic, and the mechanical solutions are very expensive. A global 10 Hz orbit feedback system consisting of 36 beam position monitors (BPMs) and 12 small dedicated dipole corrector magnets in each of the two 3.8 km circumference counter-rotating rings has been developed and commissioned in February 2011. A description of the system architecture and results with beam will be discussed.

  17. Status of superconducting magnet development (SSC, RHIC, LHC)

    International Nuclear Information System (INIS)

    Wanderer, P.

    1993-01-01

    This paper summarize recent superconducting accelerator magnet construction and test activities at the Superconducting Super Collider Laboratory (SSC), the Large Hadron Collider at CERN (LHC), and the Relativistic Heavy Ion Collider at Brookhaven (RHIC). Future plan are also presented

  18. MACHINE PROTECTION SYSTEM FOR CONCURRENT OPERATION OF RHIC AND BLIP

    International Nuclear Information System (INIS)

    WILINSKI, M.; BELLAVIA, S.; GLENN, J.W.; MAUSNER, L.F.; UNGER, K.L.

    2005-01-01

    The Brookhaven 200MeV linac is a multipurpose machine used to inject low intensity polarized protons for RHIC (Relativistic Heavy Ion Collider), as well as to inject high intensity protons to BLIP (Brookhaven Linac Isotope Producer), a medical isotope production facility. If high intensity protons were injected to RHIC by mistake, administrative radiation limits could be exceeded or sensitive electronics could be damaged. In the past, the changeover from polarized proton to high intensity proton operation has been a lengthy process, thereby never allowing the two programs to run simultaneously. To remedy this situation and allow concurrent operation of RHIC and BLIP, an active interlock system has been designed to monitor current levels in the AGS using two current transformers with fail safe circuitry and associated electronics to inhibit beam to RHIC if high intensity currents are detected

  19. Machine Protection System for Concurrent Operation of RHIC and BLIP

    CERN Document Server

    Wilinski, Michelle; Glenn, Joseph; Mausner, Leonard; Unger, Kerry

    2005-01-01

    The Brookhaven 200 MeV linac is a multipurpose machine used to inject low intensity polarized protons ultimately ending up in RHIC as well as to inject high intensity protons to BLIP, a medical isotope production facility. If high intensity protons were injected to RHIC by mistake, administrative radiation limits could be exceeded or sensitive electronics could be damaged. In the past, the changeover from polarized proton to high intensity proton operation has been a lengthy process, thereby never allowing the two programs to run simultaneously. To remedy this situation and allow for concurrent operation of RHIC and BLIP, an active interlock system has been designed to monitor current levels in the AGS using two current transformers with fail safe circuitry and associated electronics to inhibit beam to RHIC if high intensity is detected.

  20. Experience with IBS-suppression lattice in RHIC

    International Nuclear Information System (INIS)

    Litvinenko, V.N.; Luo, Y.; Ptitsyn, V.; Satogata, T.; Tepikian, S.; Bai, M.; Bruno, D.; Cameron, P.; Connolly, R.; Della Penna, A.; Drees, A.; Fedotov, A.; Ganetis, G.; Hoff, L.; Louie, W.; Malitsky, N.; Marr, G.; Marusic, A.; Montag, C.; Pilat, F.; Roser, T.; Trbojevic, D.; Tsoupas, N.

    2008-01-01

    An intra-beam scattering (IBS) is the limiting factor of the luminosity lifetime for RHIC operating with heavy ions. In order to suppress the IBS we designed and implemented new lattice with higher betatron tunes. This lattice had been developed during last three years and had been used for gold ions in yellow ring of the RHIC during d-Au part of the RHIC Run-8. The use of this lattice allowed both significant increases in the luminosity lifetime and the luminosity levels via reduction of beta-stars in the IPS. In this paper we report on the development, the tests and the performance of IBS-suppression lattice in RHIC, including the resulting increases in the peak and the average luminosity. We also report on our plans for future steps with the IBS suppression

  1. Theoretical perspective on RHIC [relativistic heavy ion collider] physics

    International Nuclear Information System (INIS)

    Dover, C.B.

    1990-10-01

    We discuss the status of the relativistic heavy ion collider (RHIC) project at Brookhaven, and assess some key experiments which propose to detect the signatures of a transient quark-gluon plasma (QGP) phase in such collisions. 24 refs

  2. Status of superconducting magnet development (SSC, RHIC, LHC)

    International Nuclear Information System (INIS)

    Wanderer, P.

    1993-01-01

    This paper summarizes recent superconducting accelerator magnet construction and test activities at the Superconducting Super Collider Laboratory (SSC), the Large Hardon Collider at CERN (LHC), and the Relativistic Heavy Ion Collider at Brookhaven (RHIC). Future plans are also presented

  3. Pharmacokinetics of Snake Venom

    Directory of Open Access Journals (Sweden)

    Suchaya Sanhajariya

    2018-02-01

    Full Text Available Understanding snake venom pharmacokinetics is essential for developing risk assessment strategies and determining the optimal dose and timing of antivenom required to bind all venom in snakebite patients. This review aims to explore the current knowledge of snake venom pharmacokinetics in animals and humans. Literature searches were conducted using EMBASE (1974–present and Medline (1946–present. For animals, 12 out of 520 initially identified studies met the inclusion criteria. In general, the disposition of snake venom was described by a two-compartment model consisting of a rapid distribution phase and a slow elimination phase, with half-lives of 5 to 48 min and 0.8 to 28 h, respectively, following rapid intravenous injection of the venoms or toxins. When the venoms or toxins were administered intramuscularly or subcutaneously, an initial absorption phase and slow elimination phase were observed. The bioavailability of venoms or toxins ranged from 4 to 81.5% following intramuscular administration and 60% following subcutaneous administration. The volume of distribution and the clearance varied between snake species. For humans, 24 out of 666 initially identified publications contained sufficient information and timed venom concentrations in the absence of antivenom therapy for data extraction. The data were extracted and modelled in NONMEM. A one-compartment model provided the best fit, with an elimination half-life of 9.71 ± 1.29 h. It is intended that the quantitative information provided in this review will provide a useful basis for future studies that address the pharmacokinetics of snakebite in humans.

  4. Snake Venom Metalloproteinases

    OpenAIRE

    Gâz Florea Şerban Andrei; Gâz Florea Adriana; Kelemen Hajnal; Muntean Daniela-Lucia

    2016-01-01

    As more data are generated from proteome and transcriptome analysis revealing that metalloproteinases represent most of the Viperid and Colubrid venom components authors decided to describe in a short review a classification and some of the multiple activities of snake venom metalloproteinases. SVMPs are classified in three major classes (P-I, P-II and P-III classes) based on the presence of various domain structures and according to their domain organization. Furthermore, P-II and P-III clas...

  5. Reproductive strategies in snakes.

    Science.gov (United States)

    Shine, Richard

    2003-05-22

    Snakes of both sexes display remarkable flexibility and diversity in their reproductive tactics. Many features of reproduction in female snakes (such as reproductive mode and frequency, seasonality and multiple mating) allow flexible maternal control. For example, females can manipulate not only the genotypes of their offspring (through mate choice or enhanced sperm competition) but also the phenotypes of their offspring (through allocation 'decisions', behavioural and physiological thermoregulation, and nest-site selection). Reliance on stored energy ('capital') to fuel breeding results in low frequencies of female reproduction and, in extreme cases, semelparity. A sophisticated vomeronasal system not only allows male snakes to locate reproductive females by following scent trails, but also facilitates pheromonally mediated mate choice by males. Male-male rivalry takes diverse forms, including female mimicry and mate guarding; combat bouts impose strong selection for large body size in males of some species. Intraspecific (geographical) variation and phenotypic plasticity in a wide array of reproductive traits (offspring size and number; reproductive frequency; incidence of multiple mating; male tactics such as mate guarding and combat; mate choice criteria) provide exceptional opportunities for future studies.

  6. Thermal and prompt photons at RHIC and the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Paquet, Jean-François [Department of Physics & Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States); Department of Physics, McGill University, 3600 University Street, Montreal, Quebec, H3A2T8 (Canada); Shen, Chun [Department of Physics, McGill University, 3600 University Street, Montreal, Quebec, H3A2T8 (Canada); Denicol, Gabriel [Department of Physics, McGill University, 3600 University Street, Montreal, Quebec, H3A2T8 (Canada); Physics Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Luzum, Matthew [Universidade de Santiago de Compostela, E-15706 Santiago de Compostela, Galicia-Spain (Spain); Universidade de São Paulo, Rua do Matão Travessa R, no. 187, 05508-090, Cidade Universitária, São Paulo (Brazil); Schenke, Björn [Physics Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Jeon, Sangyong; Gale, Charles [Department of Physics, McGill University, 3600 University Street, Montreal, Quebec, H3A2T8 (Canada)

    2016-12-15

    Thermal and prompt photon production in heavy ion collisions is evaluated and compared with measurements from both RHIC and the LHC. An event-by-event hydrodynamical model of heavy ion collisions that includes shear and bulk viscosities is used, along with up-to-date photon emission rates. Larger tension with measurements is observed at RHIC than at the LHC. The center-of-mass energy and centrality dependence of thermal and prompt photons is investigated.

  7. MEASURING LOCAL GRADIENT AND SKEW QUADRUPOLE ERRORS IN RHIC IRS

    International Nuclear Information System (INIS)

    CARDONA, J.; PEGGS, S.; PILAT, R.; PTITSYN, V.

    2004-01-01

    The measurement of local linear errors at RHIC interaction regions using an ''action and phase'' analysis of difference orbits has already been presented [2]. This paper evaluates the accuracy of this technique using difference orbits that were taken when known gradient errors and skew quadrupole errors were intentionally introduced. It also presents action and phase analysis of simulated orbits when controlled errors are intentionally placed in a RHIC simulation model

  8. Tracking studies in eRHIC energy-recovery recirculator

    Energy Technology Data Exchange (ETDEWEB)

    Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brooks, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-07-13

    Beam and polarization tracking studies in eRHIC energy recovery electron recirculator are presented, based on a very preliminary design of the FFAG lattice. These simulations provide examples of some of the beam and spin optics aspects of the linear FFAG lattice concept and its application in eRHIC, they provide code benchmarking for synchrotron radiation and spin diffusion in addition, and pave the way towards end-to-end 6-D(phasespace)+3D(spin) tracking simulations.

  9. SYNTHESIZER CONTROLLED BEAM TRANSFER FROM THE AGS TO RHIC

    International Nuclear Information System (INIS)

    DELONG, J.; BRENNAN, J.M.; FISCHER, W.; HAYES, T.; SMITH, K.; VALENTINO, S.

    2001-01-01

    To ensure minimal losses and to preserve longitudinal emittance, beam is transferred from the AGS to the RHIC bunch to bucket. This requires precision frequency and phase control for synchronization and kicker timing. The required precision is realized with a set of Direct Digital Synthesizers. Each synthesizer can be frequency and phase modulated to align the AGS bunch to the target bucket in the RHIC phase

  10. Snakes Have Feelings, Too: Elements of a Camp Snake Program.

    Science.gov (United States)

    Allen, Robert Ross

    2001-01-01

    A camp snake program can help campers overcome their fear of snakes, and people cannot truly enjoy nature when they carry a phobia about any one part of it. It can also help overcome prejudice by teaching truth and respect, instilling compassion, and helping campers develop empathy. Advice on catching, handling, identifying, keeping, and feeding…

  11. \\'The snake will swallow you': supernatural snakes and the creation ...

    African Journals Online (AJOL)

    \\'The snake will swallow you': supernatural snakes and the creation of the Khotso legend. Felicity Wood. Abstract. No Abstract. Indilinga: African Journal of Indigenous Knowledge Systems (IAJIKS) Vol. 4(1) 2005: 347-359. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  12. Proceedings of the symposium on RHIC detector R&D

    Energy Technology Data Exchange (ETDEWEB)

    Makdisi, Y.; Stevens, A.J. [eds.

    1991-12-31

    This report contains papers on the following topics: Development of Analog Memories for RHIC Detector Front-end Electronic Systems; Monolithic Circuit Development for RHIC at Oak Ridge National Laboratory; Highly Integrated Electronics for the STAR TPC; Monolithic Readout Circuits for RHIC; New Methods for Trigger Electronics Development; Neurocomputing methods for Pattern Recognition in Nuclear Physics; The Development of a Silicon Multiplicity Detector System; The Vertex Detector for the Lepton/Photon Collaboration; Simulations of Silicon Vertex Tracker for STAR Experiment at RHIC; Calorimeter/Absorber Optimization for a RHIC Dimuon Experiment (RD-10 Project); Applications of the LAHET simulation Code to Relativistic Heavy Ion Detectors; Highly Segmented, High Resolution Time-of-Flight System; Research and Development on a Sub 100 Picosecond Time-of-Flight System Based on Silicon Avalance Diodes; Behavior of TPC`s in a High Particle Flux Environment; Generic R&D on Undoped Cesium Iodide and Lead Fluoride; and A Transition Radiation Detector for RHIC Featuring Accurate Tracking and dE/dx Particle Identification. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  13. Active internal corrector coils

    International Nuclear Information System (INIS)

    Thompson, P.A.; Cottingham, J.; Dahl, P.

    1986-01-01

    Trim or corrector coils to correct main magnet field errors and provide higher multipole fields for beam optics purposes are a standard feature of superconducting magnet accelerator systems. This paper describes some of the design and construction features of powered internal trim coils and a sampling of the test results obtained

  14. Compact stellarator coils

    International Nuclear Information System (INIS)

    Pomphrey, N.; Berry, L.A.; Boozer, A.H.

    2001-01-01

    Experimental devices to study the physics of high-beta (β>∼4%), low aspect ratio (A<∼4.5) stellarator plasmas require coils that will produce plasmas satisfying a set of physics goals, provide experimental flexibility, and be practical to construct. In the course of designing a flexible coil set for the National Compact Stellarator Experiment, we have made several innovations that may be useful in future stellarator design efforts. These include: the use of Singular Value Decomposition methods for obtaining families of smooth current potentials on distant coil winding surfaces from which low current density solutions may be identified; the use of a Control Matrix Method for identifying which few of the many detailed elements of the stellarator boundary must be targeted if a coil set is to provide fields to control the essential physics of the plasma; the use of Genetic Algorithms for choosing an optimal set of discrete coils from a continuum of potential contours; the evaluation of alternate coil topologies for balancing the tradeoff between physics objective and engineering constraints; the development of a new coil optimization code for designing modular coils, and the identification of a 'natural' basis for describing current sheet distributions. (author)

  15. Liquid rope coiling

    NARCIS (Netherlands)

    Ribe, N.M.; Habibi, M.; Bonn, D.

    2012-01-01

    A thin stream or rope of viscous fluid falling from a sufficient height onto a surface forms a steadily rotating helical coil. Tabletop laboratory experiments in combination with a numerical model for slender liquid ropes reveal that finite-amplitude coiling can occur in four distinct regimes

  16. Molecular basis of coiled-coil oligomerization-state specificity.

    Science.gov (United States)

    Ciani, Barbara; Bjelic, Saša; Honnappa, Srinivas; Jawhari, Hatim; Jaussi, Rolf; Payapilly, Aishwarya; Jowitt, Thomas; Steinmetz, Michel O; Kammerer, Richard A

    2010-11-16

    Coiled coils are extensively and successfully used nowadays to rationally design multistranded structures for applications, including basic research, biotechnology, nanotechnology, materials science, and medicine. The wide range of applications as well as the important functions these structures play in almost all biological processes highlight the need for a detailed understanding of the factors that control coiled-coil folding and oligomerization. Here, we address the important and unresolved question why the presence of particular oligomerization-state determinants within a coiled coil does frequently not correlate with its topology. We found an unexpected, general link between coiled-coil oligomerization-state specificity and trigger sequences, elements that are indispensable for coiled-coil formation. By using the archetype coiled-coil domain of the yeast transcriptional activator GCN4 as a model system, we show that well-established trimer-specific oligomerization-state determinants switch the peptide's topology from a dimer to a trimer only when inserted into the trigger sequence. We successfully confirmed our results in two other, unrelated coiled-coil dimers, ATF1 and cortexillin-1. We furthermore show that multiple topology determinants can coexist in the same trigger sequence, revealing a delicate balance of the resulting oligomerization state by position-dependent forces. Our experimental results should significantly improve the prediction of the oligomerization state of coiled coils. They therefore should have major implications for the rational design of coiled coils and consequently many applications using these popular oligomerization domains.

  17. Runaway snakes in TEXTOR-94

    NARCIS (Netherlands)

    Entrop, I.; R. Jaspers,; Cardozo, N. J. L.; Finken, K.H.

    1999-01-01

    Observations of a runaway beam confined in an island-like structure, a so-called runaway snake, are reported. The observations are made in TEXTOR-94 by measurement of synchrotron radiation emitted by these runaways. A full poloidal View allows for the study of the synchrotron pattern of the snake to

  18. Veterinary management of snake reproduction.

    Science.gov (United States)

    Stahl, Scott J

    2002-09-01

    The reptile veterinarian should approach the breeder with a comprehensive plan involving a review of proper husbandry, nutrition, record keeping, and a thorough prebreeding evaluation of the snakes. In addition, an evaluation of the reproductive strategy, assistance with confirming and monitoring gestation, and a review of potential reproductive complications will help to prepare the snake owner for a successful breeding season.

  19. Quantum snake walk on graphs

    International Nuclear Information System (INIS)

    Rosmanis, Ansis

    2011-01-01

    I introduce a continuous-time quantum walk on graphs called the quantum snake walk, the basis states of which are fixed-length paths (snakes) in the underlying graph. First, I analyze the quantum snake walk on the line, and I show that, even though most states stay localized throughout the evolution, there are specific states that most likely move on the line as wave packets with momentum inversely proportional to the length of the snake. Next, I discuss how an algorithm based on the quantum snake walk might potentially be able to solve an extended version of the glued trees problem, which asks to find a path connecting both roots of the glued trees graph. To the best of my knowledge, no efficient quantum algorithm solving this problem is known yet.

  20. Large coil task and results of testing US coils

    International Nuclear Information System (INIS)

    Haubenreich, P.N.

    1986-01-01

    The United States, EURATOM, Japan, and Switzerland have collaborated since 1978 in development of superconducting toroidal field coils for fusion reactor applications. The United States provided a test facility nd three coils; the other participants, one coil each. All coils have the same interface dimensions and performance requirements (stable at 8 T), but internal design was decided by each team. Two US coil teams chose bath-cooled NbTi, 10-kA conductors. One developed a Nb 3 Sn conductor, cooled by internal flow, rated at 18 kA. All US coils have diagnostic instrumentation and imbedded heaters that enable stability tests and simulated nuclear heating experiments. In single-coil tests, each coil operated at full current in self-field (6.4 T). In six-coil tests that began in July 1986, one US coil and the Japanese coil hve been successfully operated at full current at 8 T. The other coils have operated as background coils while awaiting their turn as test coil. Coil tests have been informative and results gratifying. The facility has capably supported coil testing and its operation has provided information that will be useful in designing future fusion systems. Coil capabilities beyond nominal design points will be determined

  1. Commercial applications for COIL

    Science.gov (United States)

    Solomon, Wayne C.; Carroll, David L.; King, D. M.; Fockler, L. A.; Stromberg, D. S.; Sexauer, M.; Milmoe, A.; Sentman, Lee H.

    2000-01-01

    The chemical oxygen-iodine laser (COIL) is a high power, fiber deliverable tool, which can be used for a number of different industrial applications. COIL is of particular interest because of its short fiber deliverable wavelength, high scaleable continuous wave power, and excellent material interaction properties. In past research the University of Illinois at Urbana-Champaign identified and decommissioning and decontamination (DD) of nuclear facilities as a primary focus for COIL technology. DD will be a major challenge in the coming decades. The use of a robotically driven fiber delivered cutting/ablation tool in contaminated areas promises to lower risks to workers for the DD mission. Further, the high cutting speed of COIL will significantly reduce the time required to cut contaminated equipment, reducing costs. The high power of COIL will permit the dismantling of thick stacks of piping and equipment as well as reactor vessels. COIL is very promising for the removal of material from contaminated surfaces, perhaps to depths thicker than an inch. Laser cutting and ablation minimizes dust and fumes, which reduces the required number of high efficiency particulate accumulator filters, thus reducing costly waste disposal. Other potential industrial applications for COIL are shipbuilding, automotive manufacturing, heavy machinery manufacturing, tasks requiring underwater cutting or welding, and there appear to be very promising applications for high powers lasers in the oil industry.

  2. Open coil traction system.

    Science.gov (United States)

    Vibhute, Pavankumar Janardan

    2012-01-01

    Sliding mechanics have become a popular method for space closure, with the development of preadjusted edgewise appliances. Furthermore, various space closing auxiliaries have been developed and extensively evaluated for their clinical efficiency. Their effectiveness is enhanced with optimum force magnitude and low load deflection rate/force decay. With the advent of nickel-titanium (Ni-Ti) springs in orthodontics, load deflection rates have been markedly reduced. To use Ni-Ti springs, clinicians have to depend upon prefabricated closed coil springs. The open coil traction system, or open coil retraction spring, is developed utilizing Ni-Ti open coil springs for orthodontic space closure. This article describes the fabrication and clinical application of the open coil traction system, which has a number of advantages. It sustains a low load deflection rate with optimum force magnitude, and its design is adjustable for a desired length and force level. It is fail-safe for both activation and deactivation (ie, it cannot be overactivated, and the decompression limit of the open coil is controlled by the operator). The open coil traction system can be offset from the mucosa to help reduce soft tissue impingement.

  3. Nanofibrous Snake Venom Hemostat

    OpenAIRE

    Kumar, Vivek A.; Wickremasinghe, Navindee C.; Shi, Siyu; Hartgerink, Jeffrey D.

    2015-01-01

    Controlling perioperative bleeding is of critical importance to minimize hemorrhaging and fatality. Patients on anticoagulant therapy such as heparin have diminished clotting potential and are at risk for hemorrhaging. Here we describe a self-assembling nanofibrous peptide hydrogel (termed SLac) that on its own can act as a physical barrier to blood loss. SLac was loaded with snake-venom derived Batroxobin (50 μg/mL) yielding a drug-loaded hydrogel (SB50). SB50 was potentiated to enhance clot...

  4. Coil spring venting arrangement

    International Nuclear Information System (INIS)

    McCugh, R.M.

    1975-01-01

    A simple venting device for trapped gas pockets in hydraulic systems is inserted through a small access passages, operated remotely, and removed completely. The device comprises a small diameter, closely wound coil spring which is pushed through a guide temporarily inserted in the access passage. The guide has a central passageway which directs the coil spring radially upward into the pocket, so that, with the guide properly positioned for depth and properly oriented, the coil spring can be pushed up into the top of the pocket to vent it. By positioning a seal around the free end of the guide, the spring and guide are removed and the passage is sealed

  5. Extending the self-assembly of coiled-coil hybrids

    NARCIS (Netherlands)

    Robson Marsden, Hana

    2009-01-01

    Of the various biomolecular building blocks in use in nature, coiled-coil forming peptides are amongst those with the most potential as building blocks for the synthetic self-assembly of nanostructures. Native coiled coils have the ability to function in, and influence, complex systems composed of

  6. JESS: Java extensible snakes system

    Science.gov (United States)

    McInerney, Tim; Akhavan Sharif, M. Reza; Pashotanizadeh, Nasrin

    2005-04-01

    Snakes (Active Contour Models) are powerful model-based image segmentation tools. Although researchers have proven them especially useful in medical image analysis over the past decade, Snakes have remained primarily in the academic world and they have not become widely used in clinical practice or widely available in commercial packages. A number of confusing and specialized variants exist and there has been no standard open-source implementation available. To address this problem, we present a Java Extensible Snakes System (JESS) that is general, portable, and extensible. The system uses Java Swing classes to allow for the rapid development of custom graphical user interfaces (GUI's). It also incorporates the Java Advanced Imaging(JAI) class library, which provide custom image preprocessing, image display and general image I/O. The Snakes algorithm itself is written in a hierarchical fashion, consisting of a general Snake class and several subclasses that span the main variants of Snakes including a new, powerful, robust subdivision-curve Snake. These subclasses can be easily and quickly extended and customized for any specific segmentation and analysis task. We demonstrate the utility of these classes for segmenting various anatomical structures from 2D medical images. We also demonstrate the effectiveness of JESS by using it to rapidly build a prototype semi-automatic sperm analysis system. The JESS software will be made publicly available in early 2005.

  7. Strangeness by Thermal Model Simulation at RHIC

    Institute of Scientific and Technical Information of China (English)

    SHI Xing-Hua; MA Yu-Gang; CAI Xiang-Zhou; CHEN Jin-Hui; MA Guo-Liang; ZHONG Chen

    2009-01-01

    The local temperature effect on strangeness enhancement in relativistic heavy ion collisions is discussed in the framework of the thermal model in which the K+ /h+ ratio becomes smaller with increasing freeze-out temperature.Considering that most strangeness particles of final-state particles are from the kaon meson,the temperature effect may play a role in strangeness production in hot dense matter where a slightly different temperature distribution in different areas could be produced by jet energy loss.This phenomenon is predicted by thermal model calculation at RHIC energy.The Ε-/φ ratio in central Au+Au collisions at 200 GeV from the thermal model depends on the freeze-out temperature obviously when γs is different.It should be one of the reasons why strangeness enhancements of Ε and φ are different though they include two strange quarks.These results indicate that thermodynamics is an important factor for strangeness production and the strangeness enhancement phenomenon.

  8. Hadron spectroscopy at RHIC and KAON

    International Nuclear Information System (INIS)

    Chung, S.U.

    1990-01-01

    A description is given of the physics opportunities at RHIC regarding quark-gluon spectroscopy. The basic idea is to isolate with appropriate triggers the sub-processes pomeron + pomeron → hadrons and γ + +γ + → hadrons with the net effective mass of hadrons in the range of 1.0 to 10.0 GeV, in order to study the hadronic states composed of u, d, c, b and gluons. The double-pomeron interactions are expected to produce glueballs and hybrids preferentially, while the two-offshell-photon initial states should couple predominantly to quarkonia and multiquark states. Of particular interest is the possibility of carrying out a CP-violation study in the B decays. The KAON facility, proposed for TRIUMF, Vancouver, Canada, is an intense hadron factory with a proton flux some 25 times higher than that available at the BNL AGS with the Booster. Therefore, a general purpose hadron spectrometer will be able to tackle the problem of studying gluonic and multiquark degrees of freedom in strangeonia. 19 refs., 3 figs

  9. A periodic table of coiled-coil protein structures.

    Science.gov (United States)

    Moutevelis, Efrosini; Woolfson, Derek N

    2009-01-23

    Coiled coils are protein structure domains with two or more alpha-helices packed together via interlacing of side chains known as knob-into-hole packing. We analysed and classified a large set of coiled-coil structures using a combination of automated and manual methods. This led to a systematic classification that we termed a "periodic table of coiled coils," which we have made available at http://coiledcoils.chm.bris.ac.uk/ccplus/search/periodic_table. In this table, coiled-coil assemblies are arranged in columns with increasing numbers of alpha-helices and in rows of increased complexity. The table provides a framework for understanding possibilities in and limits on coiled-coil structures and a basis for future prediction, engineering and design studies.

  10. Superconducting snake with the field of 75 kGs for the VEPP-2M electron-positron storage ring

    International Nuclear Information System (INIS)

    Anashin, V.V.; Vasserman, I.B.; Vlasov, A.M.

    1985-01-01

    Superconducting ''snake'' with the field of 75 kG is established in the VEPP-2M electron-positron storage ring for increase of colliding beam luminosity up to 2x10 31 cmsup(-2)sdup(-1) in the energy range from 2x200 to 2x700 MeV. The ''snake'' comprises three central magnets with the field of 75 kG and two side ones with the field of 45 kG and it is placed in one of rectilinear experimental gaps. Description of design peculiarities of the ''snake'' and its parameters are given. Parameters of beams with switched on and switched off ''snake'' as well as parameters of coils and superconducting wire are presented

  11. LHC bending magnet coil

    CERN Multimedia

    A short test version of coil of wire used for the LHC dipole magnets. The high magnetic fields needed for guiding particles around the Large Hadron Collider (LHC) ring are created by passing 12’500 amps of current through coils of superconducting wiring. At very low temperatures, superconductors have no electrical resistance and therefore no power loss. The LHC is the largest superconducting installation ever built. The magnetic field must also be extremely uniform. This means the current flowing in the coils has to be very precisely controlled. Indeed, nowhere before has such precision been achieved at such high currents. Magnet coils are made of copper-clad niobium–titanium cables — each wire in the cable consists of 9’000 niobium–titanium filaments ten times finer than a hair.

  12. Borehole induction coil transmitter

    Science.gov (United States)

    Holladay, Gale; Wilt, Michael J.

    2002-01-01

    A borehole induction coil transmitter which is a part of a cross-borehole electromagnetic field system that is used for underground imaging applications. The transmitter consists of four major parts: 1) a wound ferrite or mu-metal core, 2) an array of tuning capacitors, 3) a current driver circuit board, and 4) a flux monitor. The core is wound with several hundred turns of wire and connected in series with the capacitor array, to produce a tuned coil. This tuned coil uses internal circuitry to generate sinusoidal signals that are transmitted through the earth to a receiver coil in another borehole. The transmitter can operate at frequencies from 1-200 kHz and supplies sufficient power to permit the field system to operate in boreholes separated by up to 400 meters.

  13. Exploring new frontiers in nuclear and particle physics with the STAR detector at RHIC

    International Nuclear Information System (INIS)

    Hallman, T.J.

    1996-01-01

    The Solenoidal Tracker At RHIC (STAR) is a large acceptance collider detector scheduled to begin operation at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory in the fall of 1999. In the sections which follow, details of the STAR detector and physics program, as well as the status of the RHIC construction project will be presented

  14. On modular stellarator reactor coils

    International Nuclear Information System (INIS)

    Rau, F.; Harmeyer, E.; Kisslinger, J.; Wobig, H.

    1985-01-01

    Modular twisted coils are discussed which produce magnetic fields of the Advanced Stellarator WENDELSTEIN VII-AS type. Reducing the number coils/FP offers advantage for maintenance of coils, but increases the magnetic ripple and B m /B o . Computation of force densities within the coils of ASR and ASB yield local maximum values of about 80 and 180 MN/m 3 , respectively. A system of mutual coil support is being developed. Twisted coils in helical arrangement provide a reactor-sized HELIAC system. In order to reduce the magnetic ripple, a large number of 14 coils/FP in special arrangement is used

  15. TFTR toroidal field coil design

    International Nuclear Information System (INIS)

    Smith, G.E.; Punchard, W.F.B.

    1977-01-01

    The design of the Tokamak Fusion Test Reactor (TFTR) Toroidal Field (TF) magnetic coils is described. The TF coil is a 44-turn, spiral-wound, two-pancake, water-cooled configuration which, at a coil current of 73.3 kiloamperes, produces a 5.2-Tesla field at a major radius of 2.48 meters. The magnetic coils are installed in titanium cases, which transmit the loads generated in the coils to the adjacent supporting structure. The TFTR utilizes 20 of these coils, positioned radially at 18 0 intervals, to provide the required toroidal field. Because it is very highly loaded and subject to tight volume constraints within the machine, the coil presents unique design problems. The TF coil requirements are summarized, the coil configuration is described, and the problems highlighted which have been encountered thus far in the coil design effort, together with the development tests which have been undertaken to verify the design

  16. NCSX Toroidal Field Coil Design

    International Nuclear Information System (INIS)

    Kalish M; Rushinski J; Myatt L; Brooks A; Dahlgren F; Chrzanowski J; Reiersen W; Freudenberg K.

    2005-01-01

    The National Compact Stellarator Experiment (NCSX) is an experimental device whose design and construction is underway at the Department of Energy's Princeton Plasma Physics Laboratory (PPPL). The primary coil systems for the NCSX device consist of the twisted plasma-shaping Modular Coils, the Poloidal Field Coils, and the Toroidal Field (TF) Coils. The TF Coils are D-shaped coils wound from hollow copper conductor, and vacuum impregnated with a glass-epoxy resin system. There are 18 identical, equally spaced TF coils providing 1/R field at the plasma. They operate within a cryostat, and are cooled by LN2, nominally, to 80K. Wedge shaped castings are assembled to the inboard face of these coils, so that inward radial loads are reacted via the nesting of each of the coils against their adjacent partners. This paper outlines the TF Coil design methodology, reviews the analysis results, and summarizes how the design and analysis support the design requirements

  17. Illuminating RHIC matter with the multi-purpose direct photon

    International Nuclear Information System (INIS)

    Frantz, Justin

    2007-01-01

    In the RHIC era, the use of direct photon physics to probe heavy ion collisions has developed beyond its original scope. I make evaluations of the current state of several measurements by RHIC experiments and their associated physics implications, with a focus on their current and desired precision. At low p T , thermal photon theory is still not well constrained by the data, but improvements are on the way. At higher p T , we have been able to gain important insights, now with regards to the proposed 'jet-medium' photon sources (Fries, Muller and Srivastava 2003 Phys. Rev. Lett. 90 132301 (Preprint nucl-th/0208001); Zakharov 2004 JETP Lett. 80 617). Such predictions, as they currently exist, seem to be disfavoured by the PHENIX data; however, the idea is probably not ruled out. Finally, direct γ-jet correlations have been measured for the first time at RHIC and already show hints of medium modification

  18. The RHIC/AGS Online Model Environment: Design and Overview

    International Nuclear Information System (INIS)

    Satogata, T.; Brown, K.; Pilat, F.; Tafti Alai, A.; Tepikian, S.; Vanzeijtz

    1999-01-01

    An integrated online modeling environment is currently under development for use by AGS and RHIC physicists and commissioners. This environment combines the modeling efforts of both groups in a CDEV[1] client-server design, providing access to expected machine optics and physics parameters based on live and design machine settings. An abstract modeling interface has been designed as a set of adapters[2] around core computational modeling engines such as MAD and UAL/Teapot++[3]. This approach allows us to leverage existing survey, lattice, and magnet infrastructure, as well as easily incorporate new model engine developments. This paper describes the architecture of the RHIC/AGS modeling environment, including the application interface through CDEV and general tools for graphical interaction with the model using Tcl/Tk. Separate papers at this conference address the specifics of implementation and modeling experience for AGS and RHIC

  19. The RHIC polarized H{sup −} ion source

    Energy Technology Data Exchange (ETDEWEB)

    Zelenski, A., E-mail: zelenski@bnl.gov; Atoian, G.; Raparia, D.; Ritter, J.; Steski, D. [Brookhaven National Laboratory, Upton, New York 11973 (United States)

    2016-02-15

    A novel polarization technique had been successfully implemented for the Relativistic Heavy Ion Collider (RHIC) polarized H{sup −} ion source upgrade to higher intensity and polarization. In this technique, a proton beam inside the high magnetic field solenoid is produced by ionization of the atomic hydrogen beam (from external source) in the He-gaseous ionizer cell. Further proton polarization is produced in the process of polarized electron capture from the optically pumped Rb vapor. The use of high-brightness primary beam and large cross sections of charge-exchange cross sections resulted in production of high intensity H{sup −} ion beam of 85% polarization. The source very reliably delivered polarized beam in the RHIC Run-2013 and Run-2015. High beam current, brightness, and polarization resulted in 75% polarization at 23 GeV out of Alternating Gradient Synchrotron (AGS) and 60%-65% beam polarization at 100-250 GeV colliding beams in RHIC.

  20. Conceptual design of the Relativistic Heavy Ion Collider [RHIC

    International Nuclear Information System (INIS)

    1989-05-01

    In August 1984 Brookhaven National Laboratory submitted a proposal for the construction of a Relativistic Heavy Ion Collider (RHIC) to the US Department of Energy. A Conceptual Design Report for the RHIC facility was completed in May 1986 after detailed reviews of the machine design, and of the requirements of the physics research program. Since that time an extensive R ampersand D program has been initiated and considerable work has been carried out to refine the design and specification of the major accelerator components, as well as the needs for research detectors, and to prepare the project for construction. This document is an update of the Conceptual Design Report, incorporating the results of work carried out since the beginning of Fiscal Year 1987 when a formal R ampersand D program for the RHIC project funded by DOE was initiated

  1. Report of the stochastic cooling subgroup of the RHIC workshop

    International Nuclear Information System (INIS)

    Boussard, D.; Claus, J.; DiMassa, G.; Marriner, J.; Milutinovic, J.; Shafer, R.

    1988-01-01

    We have considered the possibility of stochastic cooling of beams for the RHIC collider. Similar studies have been carried out previously for RHIC and other bunched beam proton machines. The major motivation for cooling at RHIC is to stabilize the growth from intrabeam scattering. We find that cooling rates of the order of 500 sec are theoretically possible for beams of gold ions with γ = 100 if a cooling bandwidth of 10 GHz is used. However, the amount of microwave power which is required is large for momentum cooling and probably not practical. Considerably less power is required for slower rates. We believe that cooling times of 5000 sec for momentum cooling and 1000 sec for betatron cooling might be possible. 5 refs

  2. Transverse impedance measurement in RHIC and the AGS

    Energy Technology Data Exchange (ETDEWEB)

    Biancacci, Nicolo [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Dutheil, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mernick, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; White, S. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-05-12

    The RHIC luminosity upgrade program aims for an increase of the polarized proton luminosity by a factor 2. To achieve this goal a significant increase in the beam intensity is foreseen. The beam coupling impedance could therefore represent a source of detrimental effects for beam quality and stability at high bunch intensities. For this reason it is essential to quantify the accelerator impedance budget and the major impedance sources, and possibly cure them. In this MD note we summarize the results of the 2013 transverse impedance measurements in the AGS and RHIC. The studies have been performed measuring the tune shift as a function of bunch intensity and deriving the total accelerator machine transverse impedance. For RHIC, we could obtain first promising results of impedance localization measurements as well.

  3. Opportunities for Drell-Yan Physics at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Aschenauer, E.; Bland, L.; Crawford, H.; Goto, Y.; Eyser, O.; Kang, Z.; Vossen, A.

    2011-05-24

    Drell-Yan (DY) physics gives the unique opportunity to study the parton structure of nucleons in an experimentally and theoretically clean way. With the availability of polarized proton-proton collisions and asymmetric d+Au collisions at the Relativistic Heavy Ion Collider (RHIC), we have the basic (and unique in the world) tools to address several fundamental questions in QCD, including the expected gluon saturation at low partonic momenta and the universality of transverse momentum dependent parton distribution functions. A Drell-Yan program at RHIC is tied closely to the core physics questions of a possible future electron-ion collider, eRHIC. The more than 80 participants of this workshop focused on recent progress in these areas by both theory and experiment, trying to address imminent questions for the near and mid-term future.

  4. RHIC beam permit and quench detection communications system

    International Nuclear Information System (INIS)

    Conkling, C.R. Jr.

    1997-01-01

    A beam permit module has been developed to concentrate RHIC, subsystem sensor outputs, permit beam, and initiate emergency shutdowns. The modules accept inputs from the vacuum, cryogenic, power supply, beam loss, and superconducting magnet quench detection systems. Modules are located at equipment locations around the RHIC ring. The modules are connected by three fiberoptic communications links; a beam permit link, and two magnet power supply interlock links. During operation, carrier presence allows beam. If a RHIC subsystem detects a fault, the beam permit carrier terminates - initiating a beam dump. If the fault was a superconducting magnet quench, a power supply interlock carrier terminates - initiating an emergency magnet power dump. In addition, the master module triggers an event to cause remote sensors to log and hold data at the time-of-failure

  5. Preparing accelerator systems for the RHIC sextant commissioning

    International Nuclear Information System (INIS)

    Trbojevic, D.; Pilat, F.; Ahrens, L.

    1997-01-01

    The Relativistic Heavy Ion Collider (RHIC) construction is progressing steadily towards completion in 1999 when beams will circulate in both collider rings. One of the major tests of the RHIC project was the commissioning of the first sextant with gold ion beams in early 1997. This is a report on preparation of the RHIC accelerator systems for the first sextant test. It includes beam position monitors, timing, injection correction through the magnetic septum and kickers, current transformers, flags and the ionization beam profile monitors, beam loss monitors, beam and quench permit link system, power supply controls, and the configuration database system. The software and hardware development and coordination of the different systems before commissioning were regularly checked during bi-weekly, and (later) weekly, progress report meetings

  6. Development of NEG Coating for RHIC Experimental Beamtubes

    CERN Document Server

    Weiss, Daniel; Hseuh Hsiao Chaun; Todd, Robert J

    2005-01-01

    As RHIC beam intensity increases beyond original scope, pressure rises in some regions have been observed. The luminosity limiting pressure rises are associated with electron multi-pacting, electron stimulated desorption and beam induced desorption. Non-Evaporable Getter (NEG) coated beampipes have been proven effective to suppress pressure rise in synchrotron radiation facilities. Standard beampipes have been NEG coated by a vendor and added to many RHIC UHV regions. BNL is developing a cylindrical magnetron sputtering system to NEG coat special beryllium beampipes installed in RHIC experimental regions. It features a hollow, liquid cooled cathode producing power density of 500W/m and deposition rate of 5000 Angstrom/hr on 7.5cm OD beampipe. The cathode, a titanium tube partially covered with zirconium and vanadium ribbons, is oriented for horizontal coating of 4m long chambers. Ribbons and magnets are arranged to provide uniform sputtering distribution and deposited NEG composition. Vacuum performance of NE...

  7. Opportunities for Polarized He-3 in RHIC and EIC

    Energy Technology Data Exchange (ETDEWEB)

    Aschenauer E.; Deshpande, A.; Fischer, W.; Derbenev, S.; Milner, R.; Roser, T.; Zelenski, A.

    2011-10-01

    The workshop on opportunities for polarized He-3 in RHIC and EIC was targeted at finding practical ways of implementing and using polarized He-3 beams. Polarized He-3 beams will provide the unique opportunity for first measurements, i.e, to a full quark flavor separation measuring single spin asymmetries for p{sup +}, p{sup -} and p{sup 0} in hadron-hadron collisions. In electron ion collisions the combination of data recorded with polarized electron proton/He-3 beams allows to determine the quark flavor separated helicity and transverse momentum distributions. The workshop had sessions on polarized He-3 sources, the physics of colliding polarized He-3 beams, polarimetry, and beam acceleration in the AGS Booster, AGS, RHIC, and ELIC. The material presented at the workshop will allow making plans for the implementation of polarized He-3 beams in RHIC.

  8. Statistical analysis of RHIC beam position monitors performance

    Science.gov (United States)

    Calaga, R.; Tomás, R.

    2004-04-01

    A detailed statistical analysis of beam position monitors (BPM) performance at RHIC is a critical factor in improving regular operations and future runs. Robust identification of malfunctioning BPMs plays an important role in any orbit or turn-by-turn analysis. Singular value decomposition and Fourier transform methods, which have evolved as powerful numerical techniques in signal processing, will aid in such identification from BPM data. This is the first attempt at RHIC to use a large set of data to statistically enhance the capability of these two techniques and determine BPM performance. A comparison from run 2003 data shows striking agreement between the two methods and hence can be used to improve BPM functioning at RHIC and possibly other accelerators.

  9. Statistical analysis of RHIC beam position monitors performance

    Directory of Open Access Journals (Sweden)

    R. Calaga

    2004-04-01

    Full Text Available A detailed statistical analysis of beam position monitors (BPM performance at RHIC is a critical factor in improving regular operations and future runs. Robust identification of malfunctioning BPMs plays an important role in any orbit or turn-by-turn analysis. Singular value decomposition and Fourier transform methods, which have evolved as powerful numerical techniques in signal processing, will aid in such identification from BPM data. This is the first attempt at RHIC to use a large set of data to statistically enhance the capability of these two techniques and determine BPM performance. A comparison from run 2003 data shows striking agreement between the two methods and hence can be used to improve BPM functioning at RHIC and possibly other accelerators.

  10. Coil protection calculator for TFTR

    International Nuclear Information System (INIS)

    Marsala, R.J.; Woolley, R.D.

    1987-01-01

    A new coil protection calculator (CPC) is presented in this paper. It is now being developed for TFTR's magnetic field coils will replace the existing coil fault detector. The existing fault detector sacrifices TFTR operating capability for simplicity. The new CPC will permit operation up to the actual coil limits by accurately and continuously computing coil parameters in real-time. The improvement will allow TFTR to operate with higher plasma currents and will permit the optimization of pulse repetition rates

  11. Natural History of Pseudoboine Snakes

    Directory of Open Access Journals (Sweden)

    Marília P. Gaiarsa

    2013-01-01

    Full Text Available Even though natural history information is crucial for answering key ecological, evolutionary, and conservation questions, basic studies are still lacking for Neotropical snakes. This study aims at contributing to the knowledge of the Neotropical tribe Pseudoboini, based on literature data, analysis of museum specimens and unpublished data. The tribe is mainly composed of moderate-sized snakes, although small and large-sized snakes also occur in the clade. Mean fecundity ranged from two (Rodriguesophis iglesiasi to 29 eggs (Clelia plumbea and the species are predominantly terrestrial and nocturnal. Most species are diet specialists and lizards are the most commonly consumed prey (found in the diet of 29 species, followed by small mammals (consumed by 20 species and snakes (consumed by 18 species. Although the tribe Pseudoboini appears to be well studied, for 15 species (32% only a small amount of information or none was available. We hope that our study can motivate research on the least known species.

  12. Recombinant snake venom prothrombin activators

    OpenAIRE

    L?vgren, Ann

    2012-01-01

    Three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper Echis carinatus, trocarin from the rough-scaled snake Tropidechis carinatus, and oscutarin from the Taipan snake Oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. We have previously reported that recombinant ecarin can efficiently generate thrombin without the need ...

  13. Report on EBIS studies for a RHIC preinjector

    International Nuclear Information System (INIS)

    Beebe, E.; Hershcovitch, A.; Kponou, A.; Prelec, K.; Alessi, J.

    1995-01-01

    Bookhaven, an Electron Beam Ion Source (EBIS) is now operational. This source is being used as a test bed to answer questions relevant to the eventual design of an EBIS-based heavy ion injector for RHIC. Such a source can easily produce ions such as Au 43+ but the challenge lies in reaching intensities of interest for RHIC (3 x 10 9 particles/pulse). The source studies are planned to address issues such as scaling of the electron beam to 10 A, possible onset (and control) of instabilities, ion injection, and parametric studies of output emittance

  14. Silicon drift-chamber studies for possible use at RHIC

    International Nuclear Information System (INIS)

    Humanic, T.J.

    1990-01-01

    It is proposed to continue the program now underway at the University of Pittsburgh to study the feasibility of using silicon drift-chambers as particle tracking devices at RHIC. We are currently testing a UA6-type detector obtained from BNL and plan to also study a new device that will become available this year: a cylindrical geometry detector designed for NA45 (CERN). In addition we propose to fabricate and study a detector to be used in vertex determination for the RHIC OASIS experiment. The two-year budget for this proposal is $246.962. 5 refs., 12 figs

  15. Experimental overview on small colliding systems at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Stankus, Paul

    2016-12-15

    Beginning with the observation of ridge/flow-like features in pair correlations measurements in p+Pb, d+Au and high-density p+p events at RHIC and LHC, the last few years have seen a great surge of interest in the question of whether anything like a hot, locally-equilibrated QCD medium is formed in the small systems at collider energies. Many intriguing and suggestive results have been presented, but conclusions about medium formation must be approached with care. This presentation will attempt to summarize the experimental results from small colliding systems measured at RHIC, as part of a careful and objective evaluation of this question.

  16. Status of the quadrupoles for RHIC [Relativistic Heavy Ion Collider

    International Nuclear Information System (INIS)

    Thompson, P.A.; Cottingham, J.G.; Garber, M.

    1989-01-01

    The proposed Relativistic Heavy Ion Collider (RHIC) will require 408 regular arc quadrupoles. Two full size prototypes have been constructed and tested. The construction uses the single layer, collarless concept which has been successful in the RHIC dipoles. Both the magnets attained short sample current, which is 60% higher than the operating current. This corresponds to a gradient of 113 T/m with clear bore of 80 mm. The preliminary field measurements are in agreement with the calculations, with the exception of an unexpectedly large show sextupole. 2 refs., 5 figs., 1 tab

  17. MEASURED TRANSVERSE COUPLING IMPEDANCE OF RHIC INJECTION AND ABORT KICKERS

    International Nuclear Information System (INIS)

    HAHN, H.; DAVINO, D.

    2001-01-01

    Concerns regarding possible transverse instabilities in RHIC and the SNS pointed to the need for measurements of the transverse coupling impedance of ring components. The impedance of the RHIC injection and abort kicker was measured using the conventional method based on the S 21 forward transmission coefficient. A commercial 450 Ω twin-wire Lecher line were used and the data was interpreted via the log-formula. All measurements, were performed in test stands fully representing operational conditions including pulsed power supplies and connecting cables. The measured values for the transverse coupling impedance in kick direction and perpendicular to it are comparable in magnitude, but differ from Handbook predictions

  18. Nuclear Effects on Heavy Boson Production at RHIC and LHC

    CERN Document Server

    Zhang, X; Zhang, Xiaofei; Fai, George

    2002-01-01

    We predict W and Z transverse momentum distributions from proton-proton and nuclear collisions at RHIC and LHC. A resummation formalism with power corrections to the renormalization group equations is used. The dependence of the resummed QCD results on the non-perturbative input is very weak for the systems considered. Shadowing effects are discussed and found to be unimportant at RHIC, but important for LHC. We study the enhancement of power corrections due to multiple scattering in nuclear collisions and numerically illustrate the weak effects of the dependence on the nuclear mass.

  19. Overview of magnetic nonlinear beam dynamics in the RHIC

    International Nuclear Information System (INIS)

    Luo, Y.; Bai, M.; Beebe-Wang, J.; Bengtsson, J.; Calaga, R.; Fischer, W.; Jain, A.; Pilat, F.; Ptitsyn, V.; Malitsky, N.; Robert-Demolaize, G.; Satogata, T.; Tepikian, S.; Tomas, R.; Trbojevic, D.

    2009-01-01

    In this article we review our studies of nonlinear beam dynamics due to the nonlinear magnetic field errors in the Relativistic Heavy Ion Collider (RHIC). Nonlinear magnetic field errors, including magnetic field errors in interaction regions (IRs), chromatic sextupoles, and sextupole components from arc main dipoles are discussed. Their effects on beam dynamics and beam dynamic aperture are evaluated. The online methods to measure and correct the IR nonlinear field errors, second order chromaticities, and horizontal third order resonance are presented. The overall strategy for nonlinear corrections in RHIC is discussed

  20. Chromatic analysis and possible local chromatic correction in RHIC

    International Nuclear Information System (INIS)

    Luo, Y.; Fischer, W.; Gu, X.; Trbojevic, D.

    2011-01-01

    In this article we will answer the following questions for the RHIC polarized proton (p-p) and Au-Au run lattices: (1) what are the sources of second order chromaticities? (2) what is the dependence of second order chromaticity on the on-momentum β-beat? (3) what is the dependence of second order chromaticity on β* at IP6 and IP8? To answer these questions, we use the perturbation theory to numerically calculate the contributions of each quadrupole and sextupole to the first, second, and third order chromaticities. Possible local methods to reduce chromatic effects in RHIC ring are shortly discussed.

  1. Azimuthal anisotropy at RHIC: The first and fourth harmonics

    International Nuclear Information System (INIS)

    Adams, J.; Adler, C.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B.D.; Anderson, M.; Arkhipkin, D.; Averichev, G.S.; Badyal, S.K.; Balewski, J.; Barannikova, O.; Barnby, L.S.; Baudot, J.; Bekele, S.; Belaga, V.V.; Bellwied, R.; Berger, J.; Bezverkhny, B.I.; Bhardwaj, S.; Bhaskar, P.; Bhati, A.K.; Bichsel, H.; Billmeier, A.; Bland, L.C.; Blyth, C.O.; Bonner, B.E.; Botje, M.; Boucham, A.; Brandin, A.; Bravar, A.; Cadman, R.V.; Cai, X.Z.; Caines, H.; Calderon de la Barca Sanchez, M.; Carroll, J.; Castillo, J.; Castro, M.; Cebra, D.; Chaloupka, P.; Chattopadhyay, S.; Chen, H.F.; Chen, Y.; Chernenko, S.P.; Cherney, M.; Chikanian, A.; Choi, B.; Christie, W.; Coffin, J.P.; Cormier, T.M.; Cramer, J.G.; Crawford, H.J.; Das, D.; Das, S.; Derevschikov, A.A.; Didenko, L.; Dietel, T.; Dong, W.J.; Dong, X.; Draper, J.E.; Du, F.; Dubey, A.K.; Dunin, V.B.; Dunlop, J.C.; Dutta Majumdar, M.R.; Eckardt, V.; Efimov, L.G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Faine, V.; Faivre, J.; Fatemi, R.; Filimonov, K.; Filip, P.; Finch, E.; Fisyak, Y.; Flierl, D.; Foley, K.J.; Fu, J.; Gagliardi, C.A.; Gagunashvili, N.; Gans, J.; Ganti, M.S.; Gaudichet, L.; Germain, M.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J.E.; Grachov, O.; Grigoriev, V.; Gronstal, S.; Drosnick, D.; Guedon, M.; Guertin, S.M.; Gupta, A.; Gushin, E.; Hallman, T.J.; Hardtke, D.; Harris, J.W.; Heinz, M.; Henry, T.W.; Heppelmann, S.; Herston, T.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, G.W.; Horsley, M.; Huang, H.Z.; Huang, S.L.; Humanic, T.J.; Igo, G.; Ishihara, A.; Jacobs, P.; Jacobs, W.W.; Janik, M.; Jiang, H.; Johnson, I.; Jones, P.G.; Judd, E.G.; Kabana, S.; Kaneta, M.; Kaplan, M.; Keane, D.; Khodyrev, V.Yu.; Kiryluk, J.; Kisiel, A.; Klay, J.; Klein, S.R.; Klyachko, A.; Koetke, D.D.; Kollegger, T.; Kopytine, S.M.; Kotchenda, L.; Kovalenko, A.D.; Kramer, M.; Kravtsov, P.; Krueger, K.; Kuhn, C.; Kulikov, A.I.; Kumar, A.; et al.

    2004-01-01

    We report the first observations of the first harmonic (directed flow, v 1 ), and the fourth harmonic (v 4 ), in the azimuthal distribution of particles with respect to the reaction plane in Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). Both measurements were done taking advantage of the large elliptic flow (v 2 ) generated at RHIC. From the correlation of v 2 with v 1 it is determined that v 2 is positive, or in-plane. The integrated v 4 is about a factor of 10 smaller than v 2 . For the sixth (v 6 ) and eighth (v 8 ) harmonics upper limits on the magnitudes are reported

  2. Beam-beam collisions and crossing angles in RHIC

    International Nuclear Information System (INIS)

    Peggs, S.

    1999-01-01

    This paper evaluates the strength of head on and parasitic beam-beam collisions in RHIC when the crossing angle is zero. A non-zero crossing angle is not required in normal operation with 120 bunches, thanks to the early separation of the two beams. The RHIC lattice is shown to easily accommodate even conservatively large crossing angles, for example in beam dynamics studies, or in future operational upgrades to as many as 360 bunches per ring. A modest loss in luminosity is incurred when gold ions collide at an angle after 10 hours of storage

  3. PROPOSAL FOR AN EBIS-BASED RHIC PREINJECTOR

    International Nuclear Information System (INIS)

    ALESSI, J.G.; BEEBE, E.; KPONOU, A.; PIKIN, A.; PRELEC, K.; RAPARIA, D.; RITTER, J.; ZHANG, S.Y.

    2000-01-01

    A proposed new heavy ion preinjector for RHIC is described. The progress made at BNL on the development of an Electron Beam Ion Source (EBIS) has increased our confidence that one can build a preinjector meeting RHIC requirements using an EBIS producing intermediate charge state heavy ions. A new RFQ and Linac will be required to accelerate beams from this source to an energy sufficient for injection into the AGS Booster. These are both straightforward devices, very similar to ones already in operation at other laboratories. Injection into the Booster will occur at the same location as the existing heavy ion injection from the Tandem Van de Graaff

  4. Simulations of silicon vertex tracker for star experiment at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Odyniec, G.; Cebra, D.; Christie, W.; Naudet, C.; Schroeder, L.; Wilson, W. [Lawrence Berkeley Lab., CA (United States); Liko, D. [Institut fur Hochenenergiephysik, Vienna, (Austria); Cramer, J.; Prindle, D.; Trainor, T. [Univ. of Washington, Seattle (United States); Braithwaite, W. [Univ. of Arkansas, Little Rock (United States)

    1991-12-31

    The first computer simulations to optimize the Silicon Vertex Tracker (SVT) designed for the STAR experiment at RHIC are presented. The physics goals and the expected complexity of the events at RHIC dictate the design of a tracking system for the STAR experiment. The proposed tracking system will consist of a silicon vertex tracker (SVT) to locate the primary interaction and secondary decay vertices and to improve the momentum resolution, and a time projection chamber (TPC), positioned inside a solenoidal magnet, for continuous tracking.

  5. Cold matter effects and quarkonium production at RHIC and LHC

    Energy Technology Data Exchange (ETDEWEB)

    Dos Santos, G. S.; Mariotto, C. B. [Instituto de Matematica, Estatistica e Fisica, Universidade Federal do Rio Grande, Caixa Postal 474, CEP 96203-900, Rio Grande, RS (Brazil); Goncalves, V. P. [Instituto de Fisica e Matematica, Universidade Federal de Pelotas, Caixa Postal 354, CEP 96010-090, Pelotas, RS (Brazil)

    2013-03-25

    In this work we investigate two cold matter effects in J/{Psi} and {Upsilon} production in nuclear collisions at RHIC and LHC, namely the shadowing effect and nuclear absorption. We characterize these effects by estimating the rapidity dependence of some nuclear ratios in pA and AA collisions at RHIC and LHC, R{sub pA} = d{sigma}{sub pA}(J/{Psi},{Upsilon})/Ad{sigma}{sub pp}(J/{Psi},{Upsilon}) and R{sub AA} = d{sigma}{sub AA}(J/{Psi},{Upsilon})/A{sup 2}d{sigma}{sub pp}(J/{Psi},{Upsilon}).

  6. Flow in Au+Au collisions at RHIC

    Science.gov (United States)

    Belt Tonjes, Marguerite; the PHOBOS Collaboration; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; García, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tang, J.-L.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wolfs, F. L. H.; Wosiek, B.; Wozniak, K.; Wuosmaa, A. H.; Wysłouch, B.

    2004-08-01

    The study of flow can provide information on the initial state dynamics and the degree of equilibration attained in heavy-ion collisions. This contribution presents results for both elliptic and directed flow as determined from data recorded by the PHOBOS experiment in Au+Au runs at RHIC at \\sqrt{sNN} = 19.6, 130 and 200 GeV. The PHOBOS detector provides a unique coverage in pseudorapidity for measuring flow at RHIC. The systematic dependence of flow on pseudorapidity, transverse momentum, centrality and energy is discussed.

  7. Cutaneous Chromatophoromas in Captive Snakes.

    Science.gov (United States)

    Muñoz-Gutiérrez, J F; Garner, M M; Kiupel, M

    2016-11-01

    Chromatophoromas are neoplasms arising from pigment-bearing cells (chromatophores) of the dermis. While isolated cases have been reported in the literature, the prevalence and biological behavior of chromatophoromas in snakes are unknown. Forty-two chromatophoromas were identified among 4663 submissions (0.9%) to a private diagnostic laboratory in a 16-year period. The most commonly affected snakes were colubrids (23 cases, 55%) and vipers (8 cases, 19%). The San Francisco garter snake was the most commonly affected species (6 cases; 14% of all affected snake species and 3.7% of all garter snake submissions). No sex predilection was found. The age of 28 snakes ranged from 5 to 27 years. Single cutaneous chromatophoromas were most commonly observed and presented as pigmented cutaneous masses or plaques along any body segment. Euthanasia or death due to progressive neoplastic disease or metastasis was reported in 8 (19%) and 4 (10%) cases, respectively. The survival time of 4 animals ranged from 4 to 36 months. Microscopically, xanthophoromas, iridophoromas, melanocytic neoplasms, and mixed chromatophoromas were identified, with melanocytic neoplasms being most common. Microscopic examination alone was generally sufficient for the diagnosis of chromatophoroma, but immunohistochemistry for S-100 and PNL-2 may be helpful for diagnosing poorly pigmented cases. Moderate to marked nuclear atypia appears to be consistently present in cutaneous chromatophoromas with a high risk of metastasis, while mitotic count, lymphatic invasion, the level of infiltration, and the degree of pigmentation or ulceration were not reliable predictors of metastasis. © The Author(s) 2016.

  8. Runaway snakes in TEXTOR-94

    International Nuclear Information System (INIS)

    Entrop, I.; Jaspers, R.; Lopes Cardozo, N.J.; Finken, K.H.

    1999-01-01

    Observations of a runaway beam confined in an island-like structure, a so-called runaway snake, are reported. The observations are made in TEXTOR-94 by measurement of synchrotron radiation emitted by these runaways. A full poloidal view allows for the study of the synchrotron pattern of the snake to estimate runaway energy, pitch angle and the radius, shift and safety factor of the drift surface q D at which the runaway beam has developed. The runaway snake parameters are investigated under different current and magnetic field strength conditions. Examples are found of a runaway snake at the q D =1 and the q D =2 drift surface. The radial diffusion coefficient of runaways inside a snake is D r approx. 0.01m 2 s -1 . The rapid runaway losses in regions of (macroscopic) magnetic perturbations outside a snake and the good confinement inside an island assumed to consist of perfect nested surfaces are consistent with magnetic turbulence as the main cause for runaway transport. (author)

  9. Superconducting coil protection

    International Nuclear Information System (INIS)

    Woods, E.L.

    1975-01-01

    The protection system is based on a two-phase construction program. Phase I is the development of a reliable hardwired relay control system with a digital loop utilizing firmware and a microprocessor controller. Phase II is an expansion of the digital loop to include many heretofore unmonitored coil variables. These new monitored variables will be utilized to establish early quench detection and to formulate confirmation techniques of the quench detection mechanism. Established quench detection methods are discussed and a new approach to quench detection is presented. The new circuit is insensitive to external pulsed magnetic fields and the associated induced voltages. Reliability aspects of the coil protection system are discussed with respect to shutdowns of superconducting coil systems. Redundance and digital system methods are presented as related topics

  10. The oldest known snakes from the Middle Jurassic-Lower Cretaceous provide insights on snake evolution.

    Science.gov (United States)

    Caldwell, Michael W; Nydam, Randall L; Palci, Alessandro; Apesteguía, Sebastián

    2015-01-27

    The previous oldest known fossil snakes date from ~100 million year old sediments (Upper Cretaceous) and are both morphologically and phylogenetically diverse, indicating that snakes underwent a much earlier origin and adaptive radiation. We report here on snake fossils that extend the record backwards in time by an additional ~70 million years (Middle Jurassic-Lower Cretaceous). These ancient snakes share features with fossil and modern snakes (for example, recurved teeth with labial and lingual carinae, long toothed suborbital ramus of maxillae) and with lizards (for example, pronounced subdental shelf/gutter). The paleobiogeography of these early snakes is diverse and complex, suggesting that snakes had undergone habitat differentiation and geographic radiation by the mid-Jurassic. Phylogenetic analysis of squamates recovers these early snakes in a basal polytomy with other fossil and modern snakes, where Najash rionegrina is sister to this clade. Ingroup analysis finds them in a basal position to all other snakes including Najash.

  11. Siberian snakes for the Fermilab Main Injector

    International Nuclear Information System (INIS)

    Anferov, V.A.; Baiod, R.; Courant, E.D.

    1993-01-01

    Appropriate Siberian snakes were designed to maintain the proton beam polarization during acceleration in the Fermilab Main Injector from 8 to 150 GeV. Various snake designs were investigated to find one fitting into the 14 m straight section spaces with the required spin rotation axis and the minimum orbit excursion. The authors studied both cold and warm discrete magnet snakes as well as warm snakes with helical magnets. For the warm discrete magnet snake, obtaining small orbit excursions required a nearly longitudinal snake axis, while axes near ±45 degrees are needed when using two snakes in a ring. The authors found acceptable snakes either by using superconducting magnets or by using warm magnets with a helical dipole field

  12. Analysis, reconstruction and manipulation using arterial snakes

    KAUST Repository

    Li, Guo; Liu, Ligang; Zheng, Hanlin; Mitra, Niloy J.

    2010-01-01

    , and manipulating such arterial surfaces. The core of the algorithm is a novel deformable model, called arterial snake, that simultaneously captures the topology and geometry of the arterial objects. The recovered snakes produce a natural decomposition of the raw

  13. A hardware overview of the RHIC LLRF platform

    International Nuclear Information System (INIS)

    Hayes, T.; Smith, K.S.

    2011-01-01

    The RHIC Low Level RF (LLRF) platform is a flexible, modular system designed around a carrier board with six XMC daughter sites. The carrier board features a Xilinx FPGA with an embedded, hard core Power PC that is remotely reconfigurable. It serves as a front end computer (FEC) that interfaces with the RHIC control system. The carrier provides high speed serial data paths to each daughter site and between daughter sites as well as four generic external fiber optic links. It also distributes low noise clocks and serial data links to all daughter sites and monitors temperature, voltage and current. To date, two XMC cards have been designed: a four channel high speed ADC and a four channel high speed DAC. The new LLRF hardware was used to replace the old RHIC LLRF system for the 2009 run. For the 2010 run, the RHIC RF system operation was dramatically changed with the introduction of accelerating both beams in a new, common cavity instead of each ring having independent cavities. The flexibility of the new system was beneficial in allowing the low level system to be adapted to support this new configuration. This hardware was also used in 2009 to provide LLRF for the newly commissioned Electron Beam Ion Source.

  14. Hydrodynamic analysis of anisotropic transverse flow at RHIC

    International Nuclear Information System (INIS)

    Hirano, Tetsufumi; Tsuda, Keiichi; Kajimoto, Kohei

    2001-01-01

    By using a (3+1)-dimensional relativistic hydrodynamic model, we estimate the magnitude of (differential) elliptic flow parameter υ 2 at the BNL-RHIC energy. We compare the centrality and the transverse momentum dependence of υ 2 with the experimental data observed by the STAR Collaboration. (author)

  15. Observation of helium flow induced beam orbit oscillations at RHIC

    International Nuclear Information System (INIS)

    Montag, C.; Bonati, R.; Brennan, J.M.; Butler, J.; Cameron, P.; Ganetis, G.; He, P.; Hirzel, W.; Jia, L.X.; Koello, P.; Louie, W.; McIntyre, G.; Nicoletti, A.; Rank, J.; Roser, T.; Satogata, T.; Schmalzle, J.; Sidi-Yekhlef, A.; Sondericker, J.; Tallerico, T.

    2006-01-01

    Horizontal beam orbit jitter at frequencies around 10 Hz has been observed at RHIC for several years. The distinct frequencies of this jitter have been found at superconducting low-beta quadrupole triplet magnets around the ring, where they coincide with mechanical vibration modes of the cold masses. Recently, we have identified liquid helium flow as the driving force of these oscillations

  16. HIGH-CURRENT ERL-BASED ELECTRON COOLING FOR RHIC

    International Nuclear Information System (INIS)

    BEN-ZVI, I.

    2005-01-01

    The design of an electron cooler must take into account both electron beam dynamics issues as well as the electron cooling physics. Research towards high-energy electron cooling of RHIC is in its 3rd year at Brookhaven National Laboratory. The luminosity upgrade of RHIC calls for electron cooling of various stored ion beams, such as 100 GeV/A gold ions at collision energies. The necessary electron energy of 54 MeV is clearly out of reach for DC accelerator system of any kind. The high energy also necessitates a bunched beam, with a high electron bunch charge, low emittance and small energy spread. The Collider-Accelerator Department adopted the Energy Recovery Linac (ERL) for generating the high-current, high-energy and high-quality electron beam. The RHIC electron cooler ERL will use four Superconducting RF (SRF) 5-cell cavities, designed to operate at ampere-class average currents with high bunch charges. The electron source will be a superconducting, 705.75 MHz laser-photocathode RF gun, followed up by a superconducting Energy Recovery Linac (ERL). An R and D ERL is under construction to demonstrate the ERL at the unprecedented average current of 0.5 amperes. Beam dynamics performance and luminosity enhancement are described for the case of magnetized and non-magnetized electron cooling of RHIC

  17. BEAM-BASED MEASUREMENTS OF PERSISTENT CURRENT DECAY IN RHIC

    International Nuclear Information System (INIS)

    FISCHER, W.; JAIN, A.; TEPIKIAN, S.

    2001-01-01

    The two RHIC rings are equipped with superconducting dipole magnets. At injection, induced persistent currents in these magnets lead to a sextupole component. As the persistent currents decay with time, the horizontal and vertical chromaticities change. From magnet measurements of persistent current decays, chromaticity changes in the machine are estimated and compared with chromaticity measurements

  18. RHIC Workshop: experiments for a relativistic heavy ion collider

    International Nuclear Information System (INIS)

    Haustein, P.E.; Woody, C.L.

    1985-01-01

    Separate abstracts were prepared for individual papers in this workshop proceedings, covering such topics as: calorimeter-based experiments, dimuon detection, large magnetic spectrometers, experiments in the fragmentation region, two-photon physics, and theoretical questions relevant to experimental work at the RHIC

  19. Possible origin of RHIC Rout/Rsid HBT results

    International Nuclear Information System (INIS)

    Sandra S. Padula

    2002-01-01

    The effects of opacity of the nuclei together with a blackbody type of emission along the system history are considered as a means to explain the ratio R out =R sid observed by STAR and PHENIX collaborations at RHIC. Within our model, no flow is required to explain the data trend of this ratio for large surface emissivities

  20. Possible origin of RHIC Rout/Rsid HBT results

    International Nuclear Information System (INIS)

    Padula, Sandra S.

    2003-01-01

    The effects of opacity of the nuclei together with a blackbody type of emission along the system history are considered as a means to explain the ratio R out /R sid observed by STAR and PHENIX collaborations at RHIC. Within our model, no flow is required to explain the data trend of this ratio for large surface emissivities

  1. POSSIBLE ORIGIN OF RHIC R OUT / R SID HBT RESULTS

    International Nuclear Information System (INIS)

    PADULA, S.

    2002-01-01

    The effects of opacity of the nuclei together with a blackbody type of emission along the system history are considered as a means to explain the ratio R out /R sid observed by STAR and PHENIX collaborations at RHIC. Within our model, no flow is required to explain the data trend of this ratio for large surface emissivities

  2. Jet Tomography versus Holography at RHIC and LHC

    Directory of Open Access Journals (Sweden)

    Torrieri G.

    2011-04-01

    Full Text Available We compare pQCD based jet tomography to AdS/CFT based jet holography approach to address the heavy quark jet puzzle and discuss future tests at RHIC and LHC that could help decide which paradigm can provide the most consistent quantitative theory to explain modification of jet observabkles in high energy nuclear collisions.

  3. Computational Studies of Snake Venom Toxins

    OpenAIRE

    Paola G. Ojeda; David Ramírez; Jans Alzate-Morales; Julio Caballero; Quentin Kaas; Wendy González

    2017-01-01

    Most snake venom toxins are proteins, and participate to envenomation through a diverse array of bioactivities, such as bleeding, inflammation, and pain, cytotoxic, cardiotoxic or neurotoxic effects. The venom of a single snake species contains hundreds of toxins, and the venoms of the 725 species of venomous snakes represent a large pool of potentially bioactive proteins. Despite considerable discovery efforts, most of the snake venom toxins are still uncharacterized. Modern bioinformatics t...

  4. NET model coil test possibilities

    International Nuclear Information System (INIS)

    Erb, J.; Gruenhagen, A.; Herz, W.; Jentzsch, K.; Komarek, P.; Lotz, E.; Malang, S.; Maurer, W.; Noether, G.; Ulbricht, A.; Vogt, A.; Zahn, G.; Horvath, I.; Kwasnitza, K.; Marinucci, C.; Pasztor, G.; Sborchia, C.; Weymuth, P.; Peters, A.; Roeterdink, A.

    1987-11-01

    A single full size coil for NET/INTOR represents an investment of the order of 40 MUC (Million Unit Costs). Before such an amount of money or even more for the 16 TF coils is invested as much risks as possible must be eliminated by a comprehensive development programme. In the course of such a programme a coil technology verification test should finally prove the feasibility of NET/INTOR TF coils. This study report is almost exclusively dealing with such a verification test by model coil testing. These coils will be built out of two Nb 3 Sn-conductors based on two concepts already under development and investigation. Two possible coil arrangements are discussed: A cluster facility, where two model coils out of the two Nb 3 TF-conductors are used, and the already tested LCT-coils producing a background field. A solenoid arrangement, where in addition to the two TF model coils another model coil out of a PF-conductor for the central PF-coils of NET/INTOR is used instead of LCT background coils. Technical advantages and disadvantages are worked out in order to compare and judge both facilities. Costs estimates and the time schedules broaden the base for a decision about the realisation of such a facility. (orig.) [de

  5. 33 CFR 117.1058 - Snake River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Snake River. 117.1058 Section 117... OPERATION REGULATIONS Specific Requirements Washington § 117.1058 Snake River. (a) The draw of the Burlington Northern Santa Fe railroad bridge across the Snake River at mile 1.5 between Pasco and Burbank is...

  6. 33 CFR 117.331 - Snake Creek.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Snake Creek. 117.331 Section 117.331 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.331 Snake Creek. The draw of the Snake Creek...

  7. Coyotes Are Afraid of Little Snakes.

    Science.gov (United States)

    Weewish Tree, 1979

    1979-01-01

    Wichita tale of a contest between Coyote and Small Snake to see whose teeth are strongest. They bite each other, and soon big, strong Coyote is dead from the poisoned bite of the tiny snake. Explains why, from that time onward, coyotes have been afraid of little snakes. (DS)

  8. Trim coil power supplies

    International Nuclear Information System (INIS)

    Haisler, R.; Peeler, H.; Zajicek, W.

    1985-01-01

    The 18 trim coil power supplies have been constructed and are now in place in the K500 pit and pit mezzanine. Final wiring of the primary power and control power is proceeding along with installation of cooling water supplies. The supplies are expected to be ready for final testing into resistive loads at the beginning of June, 1985

  9. New practicable Siberian Snake schemes

    International Nuclear Information System (INIS)

    Steffen, K.

    1983-07-01

    Siberian Snake schemes can be inserted in ring accelerators for making the spin tune almost independent of energy. Two such schemes are here suggested which lend particularly well to practical application over a wide energy range. Being composed of horizontal and vertical bending magnets, the proposed snakes are designed to have a small maximum beam excursion in one plane. By applying in this plane a bending correction that varies with energy, they can be operated at fixed geometry in the other plane where most of the bending occurs, thus avoiding complicated magnet motion or excessively large magnet apertures that would otherwise be needed for large energy variations. The first of the proposed schemes employs a pair of standard-type Siberian Snakes, i.e. of the usual 1st and 2nd kind which rotate the spin about the longitudinal and the transverse horizontal axis, respectively. The second scheme employs a pair of novel-type snakes which rotate the spin about either one of the horizontal axes that are at 45 0 to the beam direction. In obvious reference to these axes, they are called left-pointed and right-pointed snakes. (orig.)

  10. Molecular Identification of Cryptosporidium Species from Pet Snakes in Thailand

    OpenAIRE

    Yimming, Benjarat; Pattanatanang, Khampee; Sanyathitiseree, Pornchai; Inpankaew, Tawin; Kamyingkird, Ketsarin; Pinyopanuwat, Nongnuch; Chimnoi, Wissanuwat; Phasuk, Jumnongjit

    2016-01-01

    Cryptosporidium is an important pathogen causing gastrointestinal disease in snakes and is distributed worldwide. The main objectives of this study were to detect and identify Cryptosporidium species in captive snakes from exotic pet shops and snake farms in Thailand. In total, 165 fecal samples were examined from 8 snake species, boa constrictor (Boa constrictor constrictor), corn snake (Elaphe guttata), ball python (Python regius), milk snake (Lampropeltis triangulum), king snake (Lampropel...

  11. Eccentric Coil Test Facility (ECTF)

    International Nuclear Information System (INIS)

    Burn, P.B.; Walstrom, P.L.; Anderson, W.C.; Marguerat, E.F.

    1975-01-01

    The conceptual design of a facility for testing superconducting coils under some conditions peculiar to tokamak systems is given. A primary element of the proposed facility is a large 25 MJ background solenoid. Discussions of the mechanical structure, the stress distribution and the thermal stability for this coil are included. The systems for controlling the facility and diagnosing test coil behavior are also described

  12. Modular coils: a promising toroidal-reactor-coil system

    International Nuclear Information System (INIS)

    Chu, T.K.; Furth, H.P.; Johnson, J.L.; Ludescher, C.; Weimer, K.E.

    1981-04-01

    The concept of modular coils originated from a need to find reactor-relevant stellarator windings, but its usefulness can be extended to provide an externally applied, additional rotational transform in tokamaks. Considerations of (1) basic principles of modular coils, (2) types of coils, (3) types of configurations (general, helically symmetric, helically asymmetric, with magnetic well, with magnetic hill), (4) types of rotational transform profile, and (5) structure and origin of ripples are given. These results show that modular coils can offer a wide range of vacuum magnetic field configurations, some of which cannot be obtained with the classical stellarator or torsatron coil configuration

  13. Optimization of Coil Element Configurations for a Matrix Gradient Coil.

    Science.gov (United States)

    Kroboth, Stefan; Layton, Kelvin J; Jia, Feng; Littin, Sebastian; Yu, Huijun; Hennig, Jurgen; Zaitsev, Maxim

    2018-01-01

    Recently, matrix gradient coils (also termed multi-coils or multi-coil arrays) were introduced for imaging and B 0 shimming with 24, 48, and even 84 coil elements. However, in imaging applications, providing one amplifier per coil element is not always feasible due to high cost and technical complexity. In this simulation study, we show that an 84-channel matrix gradient coil (head insert for brain imaging) is able to create a wide variety of field shapes even if the number of amplifiers is reduced. An optimization algorithm was implemented that obtains groups of coil elements, such that a desired target field can be created by driving each group with an amplifier. This limits the number of amplifiers to the number of coil element groups. Simulated annealing is used due to the NP-hard combinatorial nature of the given problem. A spherical harmonic basis set up to the full third order within a sphere of 20-cm diameter in the center of the coil was investigated as target fields. We show that the median normalized least squares error for all target fields is below approximately 5% for 12 or more amplifiers. At the same time, the dissipated power stays within reasonable limits. With a relatively small set of amplifiers, switches can be used to sequentially generate spherical harmonics up to third order. The costs associated with a matrix gradient coil can be lowered, which increases the practical utility of matrix gradient coils.

  14. Siberian Snakes in high-energy accelerators

    International Nuclear Information System (INIS)

    Mane, S R; Shatunov, Yu M; Yokoya, K

    2005-01-01

    We review modern techniques to accelerate spin-polarized beams to high energy and to preserve their polarization in storage rings. Crucial to the success of such work is the use of so-called Siberian Snakes. We explain these devices and the reason for their necessity. Closely related to Snakes is the concept of 'spin rotators'. The designs and merits of several types of Snakes and spin rotators are examined. Theoretical work with Snakes and spin rotators, and experimental results from several storage rings, are reviewed, including the so-called Snake resonances. (topical review)

  15. First test of the Siberian Snake concept

    International Nuclear Information System (INIS)

    Krisch, A.D.

    1990-01-01

    Test results of the Siberian Snake concept at the Indiana University Cooler Ring are presented. The Siberian Snake is a clever and interesting concept for accelerating polarized protons to high energy. Thus it would be especially useful at TeV energies where there are thousands of depolarizing resonances. The Snake is the device which job is to rotate the proton's spin by 180 deg. every time the proton goes around the ring. The Snake's main element is the superconducting solenoid magnet. Examples of the Siberian Snake overcoming depolarizing resonances are presented. 6 refs.; 24 figs

  16. Toxin synergism in snake venoms

    DEFF Research Database (Denmark)

    Laustsen, Andreas Hougaard

    2016-01-01

    Synergism between venom toxins exists for a range of snake species. Synergism can be derived from both intermolecular interactions and supramolecular interactions between venom components, and can be the result of toxins targeting the same protein, biochemical pathway or physiological process. Few...... simple systematic tools and methods for determining the presence of synergism exist, but include co-administration of venom components and assessment of Accumulated Toxicity Scores. A better understanding of how to investigate synergism in snake venoms may help unravel strategies for developing novel...

  17. [Bites of venomous snakes in Switzerland].

    Science.gov (United States)

    Plate, Andreas; Kupferschmidt, Hugo; Schneemann, Markus

    2016-06-08

    Although snake bites are rare in Europe, there are a constant number of snake bites in Switzerland. There are two domestic venomous snakes in Switzerland: the aspic viper (Vipera aspis) and the common European adder (Vipera berus). Bites from venomous snakes are caused either by one of the two domestic venomous snakes or by an exotic venomous snake kept in a terrarium. Snake- bites can cause both a local and/or a systemic envenoming. Potentially fatal systemic complications are related to disturbances of the hemostatic- and cardiovascular system as well as the central or peripheral nervous system. Beside a symptomatic therapy the administration of antivenom is the only causal therapy to neutralize the venomous toxins.

  18. Snake Robots Modelling, Mechatronics, and Control

    CERN Document Server

    Liljebäck, Pål; Stavdahl, Øyvind; Gravdahl, Jan Tommy

    2013-01-01

    Snake Robots is a novel treatment of theoretical and practical topics related to snake robots: robotic mechanisms designed to move like biological snakes and able to operate in challenging environments in which human presence is either undesirable or impossible. Future applications of such robots include search and rescue, inspection and maintenance, and subsea operations. Locomotion in unstructured environments is a focus for this book. The text targets the disparate muddle of approaches to modelling, development and control of snake robots in current literature, giving a unified presentation of recent research results on snake robot locomotion to increase the reader’s basic understanding of these mechanisms and their motion dynamics and clarify the state of the art in the field. The book is a complete treatment of snake robotics, with topics ranging from mathematical modelling techniques, through mechatronic design and implementation, to control design strategies. The development of two snake robots is de...

  19. A description of parasites from Iranian snakes.

    Science.gov (United States)

    Nasiri, Vahid; Mobedi, Iraj; Dalimi, Abdolhossein; Mirakabadi, Abbas Zare; Ghaffarifar, Fatemeh; Teymurzadeh, Shohreh; Karimi, Gholamreza; Abdoli, Amir; Paykari, Habibollah

    2014-12-01

    Little is known of the parasitic fauna of terrestrial snakes in Iran. This study aimed to evaluate the parasitic infection rates of snakes in Iran. A total of 87 snakes belonging to eight different species, that were collected between May 2012 and September 2012 and died after the hold in captivity, under which they were kept for taking poisons, were examined for the presence of gastrointestinal and blood parasites. According to our study 12 different genera of endoparasites in 64 (73.56%) of 87 examined snakes were determined. Forty one snakes (47.12%) had gastrointestinal parasites. In prepared blood smears, it was found that in 23 (26.43%) of 87 examined snakes there are at least one hemoparasite. To our knowledge, these are the first data on the internal parasitic fauna of Iranian terrestrial snakes and our findings show a higher prevalence of these organisms among them. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Snake fungal disease: an emerging threat to wild snakes.

    Science.gov (United States)

    Lorch, Jeffrey M; Knowles, Susan; Lankton, Julia S; Michell, Kathy; Edwards, Jaime L; Kapfer, Joshua M; Staffen, Richard A; Wild, Erik R; Schmidt, Katie Z; Ballmann, Anne E; Blodgett, Doug; Farrell, Terence M; Glorioso, Brad M; Last, Lisa A; Price, Steven J; Schuler, Krysten L; Smith, Christopher E; Wellehan, James F X; Blehert, David S

    2016-12-05

    Since 2006, there has been a marked increase in the number of reports of severe and often fatal fungal skin infections in wild snakes in the eastern USA. The emerging condition, referred to as snake fungal disease (SFD), was initially documented in rattlesnakes, where the infections were believed to pose a risk to the viability of affected populations. The disease is caused by Ophidiomyces ophiodiicola, a fungus recently split from a complex of fungi long referred to as the Chrysosporium anamorph of Nannizziopsis vriesii (CANV). Here we review the current state of knowledge about O. ophiodiicola and SFD. In addition, we provide original findings which demonstrate that O. ophiodiicola is widely distributed in eastern North America, has a broad host range, is the predominant cause of fungal skin infections in wild snakes and often causes mild infections in snakes emerging from hibernation. This new information, together with what is already available in the scientific literature, advances our knowledge of the cause, pathogenesis and ecology of SFD. However, additional research is necessary to elucidate the factors driving the emergence of this disease and develop strategies to mitigate its impacts.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'. © 2016 The Author(s).

  1. Snake fungal disease: An emerging threat to wild snakes

    Science.gov (United States)

    Lorch, Jeffrey M.; Knowles, Susan N.; Lankton, Julia S.; Michell, Kathy; Edwards, Jaime L.; Kapfer, Joshua M.; Staffen, Richard A.; Wild, Erik R.; Schmidt, Katie Z.; Ballmann, Anne; Blodgett, Doug; Farrell, Terence M.; Glorioso, Brad M.; Last, Lisa A.; Price, Steven J.; Schuler, Krysten L.; Smith, Christopher; Wellehan, James F. X.; Blehert, David S.

    2016-01-01

    Since 2006, there has been a marked increase in the number of reports of severe and often fatal fungal skin infections in wild snakes in the eastern USA. The emerging condition, referred to as snake fungal disease (SFD), was initially documented in rattlesnakes, where the infections were believed to pose a risk to the viability of affected populations. The disease is caused byOphidiomyces ophiodiicola, a fungus recently split from a complex of fungi long referred to as the Chrysosporium anamorph of Nannizziopsis vriesii (CANV). Here we review the current state of knowledge about O. ophiodiicola and SFD. In addition, we provide original findings which demonstrate that O. ophiodiicola is widely distributed in eastern North America, has a broad host range, is the predominant cause of fungal skin infections in wild snakes and often causes mild infections in snakes emerging from hibernation. This new information, together with what is already available in the scientific literature, advances our knowledge of the cause, pathogenesis and ecology of SFD. However, additional research is necessary to elucidate the factors driving the emergence of this disease and develop strategies to mitigate its impacts.

  2. RHIC BEAM ABORT KICKER POWER SUPPLY SYSTEM COMMISSIONING EXPERIENCE AND REMAINING ISSUES

    International Nuclear Information System (INIS)

    ZHANG, W.; AHRENS, L.A.; MI, J.; OERTER, B.; SANDERS, R.; SANDBERG, J.

    2001-01-01

    The RHIC Beam Abort Kicker Power Supply Systems commissioning experience and the remaining issues will be reported in this paper. The RHIC Blue Ring Beam Abort Kicker Power Supply System initial commissioning took place in June 1999. Its identical system in Yellow Ring was brought on line during Spring 2000. Each of the RHIC Beam Abort Kicker Power Supply Systems consists of five high voltage modulators and subsystems. These systems are critical devices for RHIC machine protection and environmental protection. They are required to be effective, reliable and operating with sufficient redundancy to safely abort the beam to its beam dump at the end of accumulation or at any time when they are commanded. To deflect 66 GeV ion beam to the beam absorbers, the RHIC Beam Abort Kicker Power Supply Systems were operated at 22 kV level. The RHIC 2000 commissioning run was very successful

  3. Supporting device for Toroidal coils

    International Nuclear Information System (INIS)

    Araki, Takao.

    1985-01-01

    Purpose: To reduce the response of a toroidal coil supporting device upon earthquakes and improve the earthquake proofness in a tokamak type thermonuclear device. Constitution: Structural materials having large longitudinal modulus and enduring great stresses, for example, stainless steels are used as the toroidal coil supporting legs and heat insulating structural materials are embedded in a nuclear reactor base mats below the supporting legs. Furthermore, heat insulating concretes are spiked around the heat insulating structural materials to prevent the intrusion of heat to the toroidal coils. The toroidal coils are kept at cryogenic state and superconductive state for the conductors. In this way, the period of proper vibrations of the toroidal coils and the toroidal coil supporting structures can be shortened thereby decreasing the seismic response. Furthermore, since the strength of the supporting legs is increased, the earthquake proofness of the coils can be improved. (Kamimura, M.)

  4. Venomous Snake Bite Injuries at Kitui District Hospital | Kihiko ...

    African Journals Online (AJOL)

    Background Snake bites are a neglected public health issue in poor rural communities, and the true burden of snake bites is not known. Kitui County has a high incidence of snake bites and no functional snake bite control programs exists. Diagnostic tests for snake species identification are not available and management ...

  5. How can the odderon be detected at RHIC and LHC?

    Energy Technology Data Exchange (ETDEWEB)

    Avila, R.F.; Gauron, P.; Nicolescu, B. [CNRS, Paris (France); Pierre et Marie Curie Univ., Paris (FR). Lab. de Physique Nucleaire et des Hautes Energies (LPNHE)

    2007-01-15

    The odderon remains an elusive object, 33 years after its invention. The odderon is now a fundamental object in QCD and it has to be found experimentally if QCD is right. In the present paper, we show how to find it at RHIC and LHC. The most spectacular signature of the odderon is the predicted difference between the differential cross-sections for proton-proton and antiproton-proton at high s and moderate t. This experiment can be done by using the STAR detector at RHIC and by combining these future data with the already present UA4/2 data. The odderon could also be found by the ATLAS experiment at LHC by performing a high-precision measurement of the real part of the hadron elastic scattering amplitude at small t. (orig.)

  6. Electromagnetic radiation from nuclear collisions at RHIC energies

    CERN Document Server

    Turbide, Simon; Frodermann, Evan; Heinz, Ulrich

    2008-01-01

    The hot and dense strongly interacting matter created in collisions of heavy nuclei at RHIC energies is modeled with relativistic hydrodynamics, and the spectra of real and virtual photons produced at mid-rapidity in these events are calculated. Several different sources are considered, and their relative importance is compared. Specifically, we include jet fragmentation, jet-plasma interactions, the emission of radiation from the thermal medium and from primordial hard collisions. Our calculations consistently take into account jet energy loss, as evaluated in the AMY formalism. We obtain results for the spectra, the nuclear modification factor (R_AA), and the azimuthal anisotropy (v_2) that agree with the photon measurements performed by the PHENIX collaboration at RHIC.

  7. Matter in extremis: Ultrarelativistic nuclear collisions at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Peter; Wang, Xin-Nian

    2004-08-20

    We review the physics of nuclear matter at high energy density and the experimental search for the Quark-Gluon Plasma at the Relativistic Heavy Ion Collider (RHIC). The data obtained in the first three years of the RHIC physics program provide several lines of evidence that a novel state of matter has been created in the most violent, head-on collisions of Au nuclei at {radical}s = 200 GeV. Jet quenching and global measurements show that the initial energy density of the strongly interacting medium generated in the collision is about two orders of magnitude larger than that of cold nuclear matter, well above the critical density for the deconfinement phase transition predicted by lattice QCD. The observed collective flow patterns imply that the system thermalizes early in its evolution, with the dynamics of its expansion consistent with ideal hydrodynamic flow based on a Quark-Gluon Plasma equation of state.

  8. Reduction of beta* and increase of luminosity at RHIC

    International Nuclear Information System (INIS)

    Pilat, F.; Bai, M.; Bruno, D.; Cameron, P.; Della Penna, A.; Drees, A.; Litvinenko, V.; Luo, Y.; Malitsky, N.; Marr, G.; Ptitsyn, V.; Satogata, T.; Tepikian, S.; Trbojevic, D.

    2009-01-01

    The reduction of β* beyond the 1m design value at RHIC has been consistently achieved over the last 6 years of RHIC operations, resulting in an increase of luminosity for different running modes and species. During the recent 2007-08 deuteron-gold run the reduction to 0.70 from the design 1m achieved a 30% increase in delivered luminosity. The key ingredients allowing the reduction have been the capability of efficiently developing ramps with tune and coupling feedback, orbit corrections on the ramp, and collimation, to minimize beam losses in the final focus triplets, the main aperture limitations for the collision optics. We will describe the operational strategy used to reduce the β*, at first squeezing the beam at store, to test feasibility, followed by the operationally preferred option of squeezing the beam during acceleration, and the resulting luminosity increase. We will conclude with future plans for the beta squeeze

  9. Intra-beam Scattering Theory and RHIC Experiments

    International Nuclear Information System (INIS)

    Wei, J.; Fedotov, A.; Fischer, W.; Malitsky, N.; Parzen, G.; Qiang, J.

    2005-01-01

    Intra-beam scattering is the leading mechanism limiting the luminosity in heavy-ion storage rings like the Relativistic Heavy Ion Collider (RHIC). The multiple Coulomb scattering among the charged particles causes transverse emittance growth and longitudinal beam de-bunching and beam loss, compromising machine performance during collision. Theoretically, the original theories developed by Piwinski, Bjorken, and Mtingwa only describe the rms beam size growth of an unbounded Gaussian distribution. Equations based on the Fokker-Planck approach are developed to further describe the beam density profile evolution and beam loss. During the 2004 RHIC heavy-ion operation, dedicated IBS experiments were performed to bench-mark the rms beam size growth, beam loss, and profile evolution both for a Gaussian-like and a longitudinal hollow beam. This paper summarizes the IBS theory and discusses the experimental bench-marking results

  10. Surface emission of quark gluon plasma at RHIC and LHC

    International Nuclear Information System (INIS)

    Xiang Wenchang; Wan Renzhou; Zhou Daicui

    2008-01-01

    Within the framework of a factorization model, we study the behaviour of nuclear modification factor in Au-Au collisions at RHIC and Pb-Pb collisions at LHC. We find that the nuclear modification factor is inversely proportional to the radius of the quark-gluon plasma and is dominated by the surface emission of hard jets. We predict the nuclear modification factor P AALHS ∼0.15 in central Pb-Pb collisions at LHC. The study shows that the factorization model can be used to describe the centrality dependence of nuclear modification factor of the high transverse momentum particles produced in heavy ion collisions at both RHIC and LHC. (authors)

  11. How robust will the RHIC lattice be during commissioning?

    International Nuclear Information System (INIS)

    Ohnuma, S.

    1991-09-01

    The question raised here is whether the RHIC lattice is robust enough to make all these commissioning manipulations possible. There are of course many factors involved in answering this question in a definitive manner. The purpose of this note is to see if there are any fundamental and serious shortcomings basic to the lattice. The lattice considered here is the one presented to the workshop by Steve Tepikian and called RHIC91. More specifically, we fix nine quadrupole parameters in all insertions except in the 6 o'clock insertion where the independent parameters is sixteen. The so-called perfect matching may require fourteen parameters instead of nine but the difference is insignificant. On the other hand, if the number of parameters is reduced from sixteen to nine in the 6 o'clock insertion, the mismatch in the arc beta function becomes non-trivial. For example, the horizontal beta may vary between 40m to 60m at QF locations

  12. Generalized z-scaling and pp collisions at RHIC

    International Nuclear Information System (INIS)

    Tokarev, Mikhail; Zborovsky, Imrich

    2007-01-01

    New generalization of the z-scaling in inclusive particle production is proposed. The scaling variable z is expressed in terms of the momentum fractions x 1 and x 2 of the incoming protons. Explicit dependence of z on the momentum fractions y a and y b of the scattered and recoil constituents carried by the inclusive particle and recoil object is included. The scaling function Ψ (z) for charged and identified hadrons produced in proton-proton collisions is constructed. The scheme allows unique description of data on inclusive cross sections of charged hadrons, pions, kaons, antiprotons and lambdas produced at RHIC energies. The obtained results suggest that the z-scaling may be used as a tool for searching for new physics phenomena of particle production in high transverse momentum and high multiplicity region at proton-proton colliders RHIC and LHC. (author)

  13. Matter in extremis: Ultrarelativistic nuclear collisions at RHIC

    International Nuclear Information System (INIS)

    Jacobs, Peter; Wang, Xin-Nian

    2004-01-01

    We review the physics of nuclear matter at high energy density and the experimental search for the Quark-Gluon Plasma at the Relativistic Heavy Ion Collider (RHIC). The data obtained in the first three years of the RHIC physics program provide several lines of evidence that a novel state of matter has been created in the most violent, head-on collisions of Au nuclei at √s = 200 GeV. Jet quenching and global measurements show that the initial energy density of the strongly interacting medium generated in the collision is about two orders of magnitude larger than that of cold nuclear matter, well above the critical density for the deconfinement phase transition predicted by lattice QCD. The observed collective flow patterns imply that the system thermalizes early in its evolution, with the dynamics of its expansion consistent with ideal hydrodynamic flow based on a Quark-Gluon Plasma equation of state

  14. Upgrade of RHIC Vacuum Systems for High Luminosity Operation

    CERN Document Server

    Hseuh Hsiao Chaun; Smart, Loralie; Todd, Robert J; Weiss, Daniel

    2005-01-01

    With increasing ion beam intensity during recent RHIC operations, pressure rises of several decades were observed at most room temperature sections and at a few cold sections. The pressure rises are associated with electron multi-pacting, electron stimulated desorption and beam ion induced desorption and have been one of the major intensity and luminosity limiting factors for RHIC. Improvement of the warm sections has been carried out in the last few years. Extensive in-situ bakes, additional UHV pumping, anti-grazing ridges and beam tube solenoids have been implemented. Several hundred meters of NEG coated beam pipes have been installed and activated. Vacuum monitoring and interlock were enhanced to reduce premature beam aborts. Preliminary measures, such as pumping before cool down to reduce monolayer condensates, were also taken to suppress the pressure rises in the cold sections. The effectiveness of these measures in reducing the pressure rises during machine studies and during physics runs are discussed...

  15. ADVANCEMENT OF THE RHIC BEAM ABORT KICKER SYSTEM

    International Nuclear Information System (INIS)

    ZHANG, W.; AHRENS, L.; MI, J.; OERTER, B.; SANDBERG, J.; WARBURTON, D.

    2003-01-01

    As one of the most critical system for RHIC operation, the beam abort kicker system has to be highly available, reliable, and stable for the entire operating range. Along with the RHIC commission and operation, consistent efforts have been spend to cope with immediate issues as well as inherited design issues. Major design changes have been implemented to achieve the higher operating voltage, longer high voltage hold-off time, fast retriggering and redundant triggering, and improved system protection, etc. Recent system test has demonstrated for the first time that both blue ring and yellow ring beam abort systems have achieved more than 24 hours hold off time at desired operating voltage. In this paper, we report break down, thyratron reverse arcing, and to build a fast re-trigger system to reduce beam spreading in event of premature discharge

  16. The RHIC general purpose multiplexed analog to digital converter system

    International Nuclear Information System (INIS)

    Michnoff, R.

    1995-01-01

    A general purpose multiplexed analog to digital converter system is currently under development to support acquisition of analog signals for the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. The system consists of a custom intelligent VME based controller module (V113) and a 14-bit 64 channel multiplexed A/D converter module (V114). The design features two independent scan groups, where one scan group is capable of acquiring 64 channels at 60 Hz, concurrently with the second scan group acquiring data at an aggregate rate of up to 80 k samples/second. An interface to the RHIC serially encoded event line is used to synchronize acquisition. Data is stored in a circular static RAM buffer on the controller module, then transferred to a commercial VMEbus CPU board and higher level workstations for plotting, report Generation, analysis and storage

  17. The strongly coupled quark-gluon plasma created at RHIC

    CERN Document Server

    Heinz, Ulrich W

    2009-01-01

    The Relativistic Heavy Ion Collider (RHIC) was built to re-create and study in the laboratory the extremely hot and dense matter that filled our entire universe during its first few microseconds. Its operation since June 2000 has been extremely successful, and the four large RHIC experiments have produced an impressive body of data which indeed provide compelling evidence for the formation of thermally equilibrated matter at unprecedented temperatures and energy densities -- a "quark-gluon plasma (QGP)". A surprise has been the discovery that this plasma behaves like an almost perfect fluid, with extremely low viscosity. Theorists had expected a weakly interacting gas of quarks and gluons, but instead we seem to have created a strongly coupled plasma liquid. The experimental evidence strongly relies on a feature called "elliptic flow" in off-central collisions, with additional support from other observations. This article explains how we probe the strongly coupled QGP, describes the ideas and measurements whi...

  18. High-pT hadron spectra at RHIC: an overview

    International Nuclear Information System (INIS)

    Klay, Jennifer L

    2005-01-01

    Recent results on high transverse momentum (p T ) hadron production in p+p, d+Au and Au+Au collisions at the relativistic heavy-ion collider (RHIC) are reviewed. Comparison of the nuclear modification factors, R dAu (p T ) and R AA (p T ), demonstrates that the large suppression in central Au+Au collisions is due to strong final-state effects. Theoretical models which incorporate jet quenching via gluon bremsstrahlung in the dense partonic medium that is expected in central Au+Au collisions at ultra-relativistic energies are shown to reproduce the shape and magnitude of the observed suppression over the range of collision energies so far studied at RHIC

  19. Optimization of the Phase Advance Between RHIC Interaction Points

    CERN Document Server

    Tomas, Rogelio

    2005-01-01

    We consider the scenario of having two identical Interaction Points (IPs) in the Relativistic Heavy Ion Collider (RHIC). The strengths of beam-beam resonances strongly depend on the phase advance between these two IPs and therefore certain phase advances could improve beam lifetime and luminosity. We compute the dynamic aperture as function of the phase advance between these IPs to find the optimum settings. The beam-beam interaction is treated in the weak-strong approximation and a complete non-linear model of the lattice is used. For the current RHIC proton working point (0.69,0.685) the design lattice is found to have the optimum phase advance. However this is not the case for other working points.

  20. Overview of results from PHOBOS experiment at RHIC

    CERN Document Server

    Olszewski, A; Baker, M D; Barton, D S; Betts, R R; Bindel, R; Budzanowski, A; Busza, W; Carroll, A; Corbo, J; Decowski, M P; García, E; George, N; Gulbrandsen, K H; Gushue, S; Halliwell, C; Hamblen, J; Henderson, C; Hicks, D; Hofman, D J; Holzman, B; Hollis, R S; Holynski, R; Iordanova, A; Johnson, E; Kane, J L; Katzy, J; Khan, N; Kucewicz, W; Kulinich, P A; Kuo, C M; Lin, W T; Manly, S L; McLeod, D; Michalowski, J; Mignerey, A C; Mülmenstädt, J; Nouicer, R; Olszewski, A; Pak, R; Park, I C; Pernegger, H; Rafelski, M; Rbeiz, M; Reed, C; Remsberg, L P; Reuter, M; Roland, C; Roland, G; Rosenberg, L J; Sagerer, J; Sarin, P; Sawicki, P; Skulski, W; Steadman, S G; Steinberg, P; Stephans, G S F; Stodulski, M; Sukhanov, A; Tang, J L; Teng, R; Trzupek, A; Vale, C; van Nieuwenhuizen, G J; Verdier, R; Wadsworth, B; Wolfs, F L H; Wosiek, B; Wozniak, K; Wuosmaa, A H; Wyslouch, B

    2002-01-01

    An overview of results for interactions of Au+Au ions at centre-of- mass energies of square root s/sub NN/=56, 130 and 200 GeV obtained by the PHOBOS collaboration at RHIC is given. Measurements of the primary charged particle density near mid-rapidity indicate that particle production grows logarithmically with collision energy and faster than linearly with the number of interacting nucleons. Elliptic flow is found to be much stronger at RHIC than at SPS energy. The effect is strongest in peripheral events and decreases for more central collisions and emission angles $\\beta >1$. The measured anti-particle to particle ratios of production rates for pions, kaons and protons in central Au+Au interactions at square root s/sub NN/=130 GeV are compatible with the statistical model of particle production, showing an increasingly baryon-free region in mid-rapidity with the increase of collision energy. (16 refs).

  1. High-pt and jet physics from RHIC to LHC

    International Nuclear Information System (INIS)

    Estienne, M.

    2008-01-01

    The observation of the strong suppression of high-pt hadrons in heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) at BNL has motivated a large experimental program using hard probes to characterize the deconfined medium created. However, what can be denoted as 'leading particle' physics accessible at RHIC presents some limitations which motivate at higher energy the study of much more penetrating objects: jets. The gain in center-of-mass energy expected at the Large Hadron Collider (LHC) at CERN will definitively improve our understanding on how the energy is lost in the system, opening a major new window of study: the physics of jets on an event-by-event basis. We will concentrate on the expected performance for jet reconstruction in ALICE using the EMCal calorimeter.

  2. Overview of results from PHOBOS experiment at RHIC

    Science.gov (United States)

    Olszewski, Andrzej; PHOBOS Collaboration; Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Corbo, J.; Decowski, M. P.; Garcia, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Henderson, C.; Hicks, D.; Hofman, D. J.; Holzman, B.; Hollis, R. S.; Hoyński, R.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Michaowski, J.; Mignerey, A. C.; Mülmenstädt, J.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Rafelski, M.; Rbeiz, M.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Steinberg, P.; Stephans, G. S. F.; Stodulski, M.; Sukhanov, A.; Tang, J. L.; Teng, R.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wadsworth, B.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysouch, B.

    2002-07-01

    An overview of results for interactions of Au+Au ions at centre-of-mass energies of √sNN = 56, 130 and 200 GeV obtained by the PHOBOS collaboration at RHIC is given. Measurements of primary charged particle density near mid-rapidity indicate that particle production grows logarithmically with collision energy and faster than linearly with the number of interacting nucleons. Elliptic flow is found to be much stronger at RHIC than at SPS energy. The effect is strongest in peripheral events and decreases for more central collisions and emission angles |η| > 1. The measured anti-particle to particle ratios of production rates for pions, kaons and protons in central Au+Au interactions at √sNN = 130 GeV are compatible with the statistical model of particle production, showing an increasingly baryon-free region in mid-rapidity with the increase of collision energy.

  3. Tolerance of Snakes to Hypergravity

    Science.gov (United States)

    Lillywhite, H. B.; Ballard, R. E.; Hargens, A. R.

    1994-01-01

    Sensitivity of carotid blood flow to +Gz (head-to-tail) acceleration was studied in six species of snakes hypothesized to show varied adaptive cardiovascular responses to gravity. Blood flow in the proximal carotid artery was measured in 15 snakes before, during and following stepwise increments of +0.25Gz force produced on a 2.4 m diameter centrifuge. During centrifugation each snake was confined to a straight position within an individually- fitted acrylic tube with the head facing the center of rotation. We measured the centrifugal force at the tail of the snake in order to quantify the maximum intensity of force gradient promoting antero-posterior pooling of blood. Tolerance to increased gravity was quantified as the acceleration force at which carotid blood flow ceased. This parameter varied according to the gravitational adaptation of species defined by their ecology and behavior. At the extremes, carotid blood flow decreased in response to increasing gravity and approached zero near +1Gz in aquatic and ground-dwelling species, whereas in climbing species carotid flow was maintained at forces in excess of +2Gz. Surprisingly, tolerant (arboreal) species withstood hypergravic forces of +2 to +3 G. for periods up to 1 h without cessation of carotid blood flow or apparent loss of consciousness. Data suggest that relatively tight skin of the tolerant species provides a natural antigravity suit which is of prime importance in counteracting Gz stress on blood circulation.

  4. Regina rigida (glossy crayfish snake)

    Science.gov (United States)

    David A. Steen; James A. Stiles; Sierra H. Stiles; Craig Guyer; Josh B. Pierce; D. Craig Rudolph; Lora L. Smith

    2011-01-01

    The overland movements and upland habitat use of wetland-associated reptiles has important conservation implications (Semlitsch and Bodie 2003. Conserv. BioI. 17:1219-1228). However, for many species, particularly snakes, we lack a basic understanding of spatial ecology and habitat use. Regina rigida is a poorly known species for which "observations of any kind...

  5. Snakes of the Guianan region

    NARCIS (Netherlands)

    Hoogmoed, M.S.

    1982-01-01

    The study of snaks from the Guianan region got an early start in 1705 when several species were pictured by Merian. As relatively large proportion of the snakes described by Linnaeus originated from Surinam. Interest for and knowledge of this group of animals steadily increased in the 18th and 19th

  6. The Forward GEM Tracker of STAR at RHIC

    OpenAIRE

    Simon, F.; Balewski, J.; Fatemi, R.; Hasell, D.; Kelsey, J.; Majka, R.; Page, B.; Plesko, M.; Underwood, D.; Smirnov, N.; Sowinski, J.; Spinka, H.; Surrow, B.; Visser, G.

    2008-01-01

    The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is in the process of designing and constructing a forward tracking system based on triple GEM technology. This upgrade is necessary to give STAR the capability to reconstruct and identify the charge sign of W bosons over an extended rapidity range through their leptonic decay mode into an electron (positron) and a neutrino. This will allow a detailed study of the flavor-separated spin str...

  7. Heavy ion physics at BNL, the AGS and RHIC

    International Nuclear Information System (INIS)

    Lowenstein, D.I.

    1985-01-01

    The advent of heavy ion acceleration with the AGS at Brookhaven National Laboratory in 1986 and the proposed Relativistic Heavy Ion Collider (RHIC) for 1990 brings us into a temperature and density regime well above anything yet produced and into a time domain of the early universe of 10 -13 -10 -6 seconds. The physics of high energy heavy ions range from the more traditional nuclear physics to the formation of new forms of matter. Quantum Chromodynamics (QCD) is the latest, and as of yet, the most successful theory to describe the interaction of quarks and gluons. The nature of the confinement of the quarks and gluons under extremes of temperature and density is one of the compelling reasons for this new physics program at BNL. There are reasons to believe that with collisions of heavy nuclei at energies in the 10 to 100 GeV/amu range a very large volume of approx. 10 fm 3 would be heated to 200-300 MeV and/or acquire a sufficient quark density (5-10 times normal baryon density) so that the entire contents of the volume would be deconfined and the quarks and gluons would form a plasma. The kinematic region for the extant machines and the proposed RHIC are shown. At AGS energies the baryons in colliding nuclei bring each other to rest, yielding fragmentation regions of high baryon density. These are the regions in which supernorvae and neutrons stars exist. For energies much higher, such as in RHIC, nuclei are transparent to each other and one can form a central region of almost zero baryon density, mostly pions, and very high temperature. This is the region of the early universe and the quark-gluon plasma. Design parameters and cost of the RHIC are discussed

  8. The Strongly Interacting Quark Gluon Plasma at RHIC and LHC

    Directory of Open Access Journals (Sweden)

    Tserruya Itzhak

    2014-04-01

    Full Text Available The study of heavy-ion collisions has currently unprecedented opportunities with two first class facilities, the Relativistic Heavy Ion Collider (RHIC at BNL and the Large Hadron Collider (LHC at CERN, and five large experiments ALICE, ATLAS, CMS, PHENIX and STAR producing a wealth of high quality data. Selected results recently obtained are presented on the study of flow, energy loss and direct photons.

  9. RHIC susceptibility to variations in systematic magnetic harmonic errors

    International Nuclear Information System (INIS)

    Dell, G.F.; Peggs, S.; Pilat, F.; Satogata, T.; Tepikian, S.; Trbojevic, D.; Wei, J.

    1994-01-01

    Results of a study to determine the sensitivity of tune to uncertainties of the systematic magnetic harmonic errors in the 8 cm dipoles of RHIC are reported. Tolerances specified to the manufacturer for tooling and fabrication can result in systematic harmonics different from the expected values. Limits on the range of systematic harmonics have been established from magnet calculations, and the impact on tune from such harmonics has been established

  10. NON-LINEAR MODELING OF THE RHIC INTERACTION REGIONS

    International Nuclear Information System (INIS)

    TOMAS, R.; FISCHER, W.; JAIN, A.; LUO, Y.; PILAT, F.

    2004-01-01

    For RHIC's collision lattices the dominant sources of transverse non-linearities are located in the interaction regions. The field quality is available for most of the magnets in the interaction regions from the magnetic measurements, or from extrapolations of these measurements. We discuss the implementation of these measurements in the MADX models of the Blue and the Yellow rings and their impact on beam stability

  11. An approximately 4π tracking magnetic spectrometer for RHIC

    International Nuclear Information System (INIS)

    1987-01-01

    A tracking magnetic spectrometer based on large Time Projection Chambers (TPC) is proposed to measure the momentum of charged particles emerging from the RHIC beam pipe at angles larger than four degrees and to identify the particle type for those beyond fifteen degrees with momenta up to 700 MeV/c, which is a large fraction of the final charged particles emitted by a low rapidity quark-gluon plasma

  12. Open Heavy Flavor and Quarkonia Results at RHIC

    Science.gov (United States)

    Nouicer, Rachid

    2017-12-01

    RHIC experiments carry out a comprehensive physics program which studies open heavy flavor and quarkonium production in relativistic heavy-ion collisions. The discovery at RHIC of large high-pT suppression and flow of electrons from heavy quarks flavors have altered our view of the hot and dense matter formed in central Au + Au collisions at GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. In recent years, the RHIC experiments upgraded the detectors; (1) PHENIX Collaboration installed silicon vertex tracker (VTX) at mid-rapidity region and forward silicon vertex tracker (FVTX) at the forward rapidity region, and (2) STAR Collaboration installed the heavy flavor tracker (HFT) and the muon telescope detector (MTD) both at the mid-rapidity region. With these new upgrades, both experiments have collected large data samples. These new detectors enhance the capability of heavy flavor measurements via precision tracking. The PHENIX experiments established measurements of ψ(1S) and ψ(2S) production as a function of system size, p + p, p + Al, p + Au, and 3He + Au collisions at GeV. In p/3He + A collisions at forward rapidity, we observe no difference in the ψ(2S)/ψ(1S) ratio relative to p + p collisions. At backward rapidity, where the comoving particle density is higher, we find that the ψ(2S) is preferentially suppressed by a factor of two. STAR Collaboration presents the first J/ψ and ϒ measurements in the di-muon decay channel in Au + Au collisions at GeV at mid-rapidity at RHIC. We observe clear J/ψ RAA suppression and qualitatively well described by transport models simultaneously accounting for dissociation and regeneration processes.

  13. Open Heavy Flavor and Quarkonia Results at RHIC

    Directory of Open Access Journals (Sweden)

    Nouicer Rachid

    2017-01-01

    Full Text Available RHIC experiments carry out a comprehensive physics program which studies open heavy flavor and quarkonium production in relativistic heavy-ion collisions. The discovery at RHIC of large high-pT suppression and flow of electrons from heavy quarks flavors have altered our view of the hot and dense matter formed in central Au + Au collisions at SNN=200 GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. In recent years, the RHIC experiments upgraded the detectors; (1 PHENIX Collaboration installed silicon vertex tracker (VTX at mid-rapidity region and forward silicon vertex tracker (FVTX at the forward rapidity region, and (2 STAR Collaboration installed the heavy flavor tracker (HFT and the muon telescope detector (MTD both at the mid-rapidity region. With these new upgrades, both experiments have collected large data samples. These new detectors enhance the capability of heavy flavor measurements via precision tracking. The PHENIX experiments established measurements of ψ(1S and ψ(2S production as a function of system size, p + p, p + Al, p + Au, and 3He + Au collisions at SNN=200 GeV. In p/3He + A collisions at forward rapidity, we observe no difference in the ψ(2S/ψ(1S ratio relative to p + p collisions. At backward rapidity, where the comoving particle density is higher, we find that the ψ(2S is preferentially suppressed by a factor of two. STAR Collaboration presents the first J/ψ and ϒ measurements in the di-muon decay channel in Au + Au collisions at SNN=200 GeV at mid-rapidity at RHIC. We observe clear J/ψ RAA suppression and qualitatively well described by transport models simultaneously accounting for dissociation and regeneration processes.

  14. Monolithic circuit development for RHIC at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Alley, G.T.; Britton, C.L. Jr.; Kennedy, E.J.; Newport, D.F.; Wintenberg, A.L.; Young, G.R. [Oak Ridge National Laboratory, TN (United States)

    1991-12-31

    The work performed for RHIC at Oak Ridge National Laboratory during FY 91 is presented in this paper. The work includes preamplifier, analog memory, and analog-digital converter development for Dimuon Pad Readout, and evaluation and development of preamplifier-shapers for silicon strip readout. The approaches for implementation are considered as well as measured data for the various circuits that have been developed.

  15. Calirimeter/absorber optimization for a RHIC dimuon experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aronson, S.H.; Murtagh, M.J.; Starks, M. [Brookhaven National Lab., Upton, NY (United States); Liu, X.T.; Petitt, G.A.; Zhang, Z. [Georgia State Univ., Atlanta (United States); Ewell, L.A.; Hill, J.C.; Wohn, F.K. [Iowa State Univ., Ames (United States); Costales, J.B.; Namboodiri, M.N., Sangster, T.C.; Thomas, J.H. [Lawrence Livermore National Lab., CA (United States); Gavron, A.; Waters, L. [Los Alamos National Lab., NM (United States); Kehoe, W.L.; Steadman, S.G. [Massachusetts Institute of Technology, Cambridge (United States); Awes, T.C.; Obenshain, F.E.; Saini, S.; Young, G.R. [Oak Ridge National Lab., TN (United States); Chang, J.; Fung, S.Y.; Kang, J.H. [Univ. of California, Riverside, CA (United States); Kreke, J.; He, Xiaochun, Sorensen, S.P. [Univ. of Tennessee, Knoxville (United States); Cornell, E.C.; Maguire, C.F. [Vanderbilt Univ., Nashville, TN (United States)

    1991-12-31

    The RD-10 R&D effort on calorimeter/absorber optimization for a RHIC experiment had an extended run in 1991 using the A2 test beam at the AGS. Measurements were made of the leakage of particles behind various model hadron calorimeters. Behavior of the calorimeter/absorber as a muon-identifier was studied. First comparisons of results from test measurements to calculated results using the GHEISHA code were made

  16. Relativistic nucleus-nucleus collisions: from the BEVALAC to RHIC

    International Nuclear Information System (INIS)

    Stock, Reinhard

    2004-01-01

    I briefly describe the initial goals of relativistic nuclear collision research, focusing on the LBL Bevatron/Bevalac facility in the 1970s. An early concept of high hadronic density fireball formation, and subsequent isentropic decay (preserving information of the high-density stage), led to an outline of physics observables that could determine the nuclear matter equation of state at several times the nuclear ground state matter density. With the advent of QCD the goal of locating and characterizing the hadron-parton deconfinement phase transformation suggested the need for higher √s, the research thus shifting to the BNL AGS and CERN SPS, and finally to RHIC at BNL. A set of physics observables is discussed where present data span the entire √s domain, from Bevalac and SIS at GSI, to high RHIC energy. Referring, selectively, to data concerning bulk hadron production, the overall √s evolution of directed and radial flow observables, and of pion pair Bose-Einstein correlation is discussed. The hadronization process is studied in the grand canonical statistical model. The resulting hadronization points in the plane T versus μ B converge onto the parton-hadron phase boundary predicted by finite μ B lattice QCD, from high SPS to RHIC energy. At lower SPS and high AGS energy a steep strangeness maximum occurs at which the Wroblewski parameter λ s ∼ 0.6; a possible connection to the QCD critical point is discussed. Finally the unique new RHIC physics is addressed: high-p T hadron suppression and jet 'tomography'

  17. Parton-hadron cascade approach at SPS and RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Nara, Yasushi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-07-01

    A parton-hadron cascade model which is the extension of hadronic cascade model incorporating hard partonic scattering based on HIJING is presented to describe the space-time evolution of parton/hadron system produced by ultra-relativistic nuclear collisions. Hadron yield, baryon stopping and transverse momentum distribution are calculated and compared with HIJING and VNI. Baryon density, energy density and temperature for RHIC are calculated within this model. (author)

  18. Synchrotron Radiation in eRHIC Interaction Region

    CERN Document Server

    Beebe-Wang, Joanne; Montag, Christoph; Rondeau, Daniel J; Surrow, Bernd

    2005-01-01

    The eRHIC currently under study at BNL consists of an electron storage ring added to the existing RHIC complex. The interaction region of this facility has to provide the required low-beta focusing while accommodating the synchrotron radiation generated by beam separation close to the interaction point. In the current design, the synchrotron radiation caused by 10GeV electrons bent by low-beta triplet magnets will be guided through the interaction region and dumped 5m downstream. However, it is unavoidable to stop a fraction of the photons at the septum where the electron and ion vacuum system are separated. In order to protect the septum and minimize the backward scattering of the synchrotron radiation, an absorber and collimation system will be employed. In this paper, we first present the overview of the current design of the eRHIC interaction region with special emphasis on the synchrotron radiation. Then the initial design of the absorber and collimation system, including their geometrical and physical p...

  19. Power systems for the RHIC first sextant test

    International Nuclear Information System (INIS)

    Schultheiss, C.; Bruno, D.; Feng, P.K.

    1997-01-01

    The first sextant test of the RHIC project is an opportunity to evaluate the many systems that must work together for the accelerator to operate. For the main dipole string, the actual main quadrupole power supply with its DSP regulator and output circuit compartment will be used. Temporary supplies will be used for the main quadrupole string, quadrupole offset, and quadrupole shunt supplies. This will let the authors both measure the performance of the main supply as well as determine the interaction among other power elements in the circuit. Correction elements will also be powered. The actual gamma-T power supplies will be used, as well as temporary supplies for the dipole correctors and sextupole supplies. Some of these units are required for beam to be transported, others are to be operated without beam to measure their performance, and how they interact with their superconducting loads. The power supply equipment, and that of other systems, required an infrastucture of AC power and output cable distribution in the RHIC tunnel, outlying service buildings, and interconnecting the tunnel to the service buildings. This note will describe the performance of the RHIC power supply systems during the sextant test, and the experience gained from this exercise

  20. SDRC I-DEAS and RHIC (Relativistic Heavy Ion Collider)

    International Nuclear Information System (INIS)

    Goggin, C.M.

    1989-01-01

    In August 1984, Brookhaven National Laboratory submitted a proposal to the Department of Energy (DOE) for the construction of a Relativistic Heavy Ion Collider (RHIC). Since then funding has continued for the detailed design of RHIC. The hardware for RHIC consists of two concentric rings of superconducting magnets in a 2.4 mile circumference with six intersections. Bunches of ions will travel in opposite directions in each of the two rings and eventually collide head on at one of the six intersections. The hardware design involves complicated facilities for liquid helium cryogens, cryostat design, and pipe systems. The greatest challenge however is the ion beam position relative to the geometric center of the rings. There are three hundred and seventy-two dipole magnets that are ten meters long and weigh 4300 Kg (4.5 tons) each. Each dipole must be positioned in the ring to ± 0.5 mm. In addition, there are four hundred and ninety-two quadrupole magnets that must be positioned to ± 0.1 mm which is a total position error. This total position error includes all the surveying and part tolerance. To accomplish this task requires detailed planning and design of the cryostats which contain each magnet and the tunnel assembly throughout the 2.4 mile circumference. The IDEAS' software package provides a way to analyze this large scale problem. 11 figs

  1. Recent RHIC in-situ coating technology developments

    CERN Document Server

    Hershcovitch, A.; Brennan, J.M.; Chawla, A.; Fischer, W.; Liaw, C-J; Meng, W.; Todd, R.; Custer, A.; Erickson, M.; Jamshidi, N.; Kobrin, P.; Laping, R.; Poole, H.J.; Jimenez, J.M.; Neupert, H.; Taborelli, M.; Yin-Vallgren, C.; Sochugov, N.

    2013-04-22

    To rectify the problems of electron clouds observed in RHIC and unacceptable ohmic heating for superconducting magnets that can limit future machine upgrades, we started developing a robotic plasma deposition technique for $in-situ$ coating of the RHIC 316LN stainless steel cold bore tubes based on staged magnetrons mounted on a mobile mole for deposition of Cu followed by amorphous carbon (a-C) coating. The Cu coating reduces wall resistivity, while a-C has low SEY that suppresses electron cloud formation. Recent RF resistivity computations indicate that 10 {\\mu}m of Cu coating thickness is needed. But, Cu coatings thicker than 2 {\\mu}m can have grain structures that might have lower SEY like gold black. A 15-cm Cu cathode magnetron was designed and fabricated, after which, 30 cm long samples of RHIC cold bore tubes were coated with various OFHC copper thicknesses; room temperature RF resistivity measured. Rectangular stainless steel and SS discs were Cu coated. SEY of rectangular samples were measured at ro...

  2. Coil Optimization for HTS Machines

    DEFF Research Database (Denmark)

    Mijatovic, Nenad; Jensen, Bogi Bech; Abrahamsen, Asger Bech

    An optimization approach of HTS coils in HTS synchronous machines (SM) is presented. The optimization is aimed at high power SM suitable for direct driven wind turbines applications. The optimization process was applied to a general radial flux machine with a peak air gap flux density of ~3T...... is suitable for which coil segment is presented. Thus, the performed study gives valuable input for the coil design of HTS machines ensuring optimal usage of HTS tapes....

  3. The Study on the Snake by TOXICON

    Directory of Open Access Journals (Sweden)

    Sung-wook Kim

    2003-06-01

    Full Text Available The study was carried out to investigate the researches of Snake which was published papers in the TOXICON(1990-2.000, one of the most famous Journal of toxicology. And the results were as follows: 1. The number related with Snake is 195papers. 2. There were great papers related wih Cobra, and next is Tigris, Viper, etc. 3. There were great papers related wih protein in the composition of snake venom. 4. There were great papers related wih neurotoxin in the research of poisonous character. 5. There were great papers related wih Viper according to the anticoagulation. 6. Eight papers were published to study the immune response of snake venom. 7. The papers of molecular study of snake venom were seven. 8. The papers of anti-snake venom study were three.

  4. Snake scales, partial exposure, and the Snake Detection Theory: A human event-related potentials study

    Science.gov (United States)

    Van Strien, Jan W.; Isbell, Lynne A.

    2017-01-01

    Studies of event-related potentials in humans have established larger early posterior negativity (EPN) in response to pictures depicting snakes than to pictures depicting other creatures. Ethological research has recently shown that macaques and wild vervet monkeys respond strongly to partially exposed snake models and scale patterns on the snake skin. Here, we examined whether snake skin patterns and partially exposed snakes elicit a larger EPN in humans. In Task 1, we employed pictures with close-ups of snake skins, lizard skins, and bird plumage. In task 2, we employed pictures of partially exposed snakes, lizards, and birds. Participants watched a random rapid serial visual presentation of these pictures. The EPN was scored as the mean activity (225–300 ms after picture onset) at occipital and parieto-occipital electrodes. Consistent with previous studies, and with the Snake Detection Theory, the EPN was significantly larger for snake skin pictures than for lizard skin and bird plumage pictures, and for lizard skin pictures than for bird plumage pictures. Likewise, the EPN was larger for partially exposed snakes than for partially exposed lizards and birds. The results suggest that the EPN snake effect is partly driven by snake skin scale patterns which are otherwise rare in nature. PMID:28387376

  5. Large superconducting coil fabrication development

    International Nuclear Information System (INIS)

    Brown, R.L.; Allred, E.L.; Anderson, W.C.; Burn, P.B.; Deaderick, R.I.; Henderson, G.M.; Marguerat, E.F.

    1975-01-01

    Toroidal fields for some fusion devices will be produced by an array of large superconducting coils. Their size, space limitation, and field requirements dictate that they be high performance coils. Once installed, accessibility for maintenance and repairs is severely restricted; therefore, good reliability is an obvious necessity. Sufficient coil fabrication will be undertaken to develop and test methods that are reliable, fast, and economical. Industrial participation will be encouraged from the outset to insure smooth transition from development phases to production phases. Initially, practice equipment for three meter bore circular coils will be developed. Oval shape coil forms will be included in the practice facility later. Equipment that is more automated will be developed with the expectation of winding faster and obtaining good coil quality. Alternate types of coil construction, methods of winding and insulating, will be investigated. Handling and assembly problems will be studied. All technology developed must be feasible for scaling up when much larger coils are needed. Experimental power reactors may need coils having six meter or larger bores

  6. Triple Halo Coil: Development and Comparison with Other TMS Coils

    Science.gov (United States)

    Rastogi, Priyam; Hadimani, Ravi; Jiles, David

    Transcranial Magnetic Stimulation (TMS) is a non-invasive stimulation technique that can be used for the treatment of various neurological disorders such as Parkinson's Disease, PTSD, TBI and anxiety by regulating synaptic activity. TMS is FDA approved for the treatment of major depressive disorder. There is a critical need to develop deep TMS coils that can stimulate deeper regions of the brain without excessively stimulating the cortex in order to provide an alternative to surgical methods. We have developed a novel multi-coil configuration called ``Triple Halo Coil'' (THC) that can stimulate deep brain regions. Investigation of induced electric and magnetic field in these regions have been achieved by computer modelling. Comparison of the results due to THC configuration have been conducted with other TMS coils such as ``Halo Coil'', circular coil and ``Figure of Eight'' coil. There was an improvement of more than 15 times in the strength of magnetic field, induced by THC configuration at 10 cm below the vertex of the head when compared with the ``Figure of Eight'' coil alone. Carver Charitable Trust.

  7. The coiled coil motif in polymer drug delivery systems

    Czech Academy of Sciences Publication Activity Database

    Pechar, Michal; Pola, Robert

    2013-01-01

    Roč. 31, č. 1 (2013), s. 90-96 ISSN 0734-9750 R&D Projects: GA ČR GA203/08/0543; GA MŠk 1M0505 Institutional research plan: CEZ:AV0Z40500505 Keywords : coiled coil * hydrophilic polymer * recombinant protein Subject RIV: CD - Macromolecular Chemistry Impact factor: 8.905, year: 2013

  8. Helical Siberian snakes using dipole magnets

    International Nuclear Information System (INIS)

    Wienands, U.

    1990-09-01

    A family of multi-twist transverse-field spin rotators using discrete bending magnets is described that can be used as Siberian snakes. By varying the number of twists, snakes with quite small excursions can be constructed at only a small penalty in the overall field integral. Examples for a 1/4-twist snake and a 3-twist snake are presented, the first suitable for a very high energy machine and the second for use in the proposed TRIUMF Kaon Factory. (Author) (3 refs.)

  9. Scientific articles of the RBRC/CCAST Symposium on Spin Physics Lattice QCD and RHIC Physics

    International Nuclear Information System (INIS)

    2003-01-01

    This volume comprises scientific articles of the symposium on spin physics, lattice QCD and RHIC physics organized by RIKEN BNL research center (RBRC) and China center of advanced science and technology (CCAST). The talks were discussing the spin structure of nucleons and other problems of RHIC physics

  10. Indiana: Siberian Snake saves spin

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1990-01-15

    A team working at the Indiana University Cooler Ring has used a 'Siberian Snake' system to accelerate a spin-polarized proton beam through two depolarizing resonances with no loss of spin. The Michigan/lndiana/Brookhaven team under Alan Krisch overcame their first imperfection resonance hurdle at 108 MeV, and in a subsequent run vanquished a further resonance at 177 MeV.

  11. Indiana: Siberian Snake saves spin

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    A team working at the Indiana University Cooler Ring has used a 'Siberian Snake' system to accelerate a spin-polarized proton beam through two depolarizing resonances with no loss of spin. The Michigan/lndiana/Brookhaven team under Alan Krisch overcame their first imperfection resonance hurdle at 108 MeV, and in a subsequent run vanquished a further resonance at 177 MeV

  12. Experimental research of specificity of fear of snake: coral snake pattern

    OpenAIRE

    Průšová, Lucie

    2013-01-01

    Due to shared coevolutionary history of snakes and primates with snakes acting as their main predators, snakes elicit fear in most of the primates, humans included. Humans are able to notice a stimulus that elicits fear, e.g., a snake, much faster. Such ability might have surely positively affected their survival in the past. In the nature, aposematic coloration acts as a warning of a dangerous prey to its predators not to devour it. The highly poisonous American coral snakes have this colora...

  13. Comparison of the Window-Frame RHIC-abort kicker with C-type Kicker

    International Nuclear Information System (INIS)

    Tsoupas, N.; McMahan, Brandon

    2014-01-01

    The high intensity proton bunches (~2.5x10 11 p/bunch ) circulating in RHIC increase the temperature of the ferrite-made RHIC-abort-kickers above the Curie point; as a result, the kickers cannot provide the required field to abort the beam at the beam dump. A team of experts in the CAD department worked on modifying the design of the window-frame RHIC-abort kicker to minimize the hysteresis losses responsible for the increase of the ferrite's temperature. In this technical note we report some results from the study of two possible modifications of the window-frame RHIC-abort kicker, and we compare these results with those of a propose C-type RHIC-abort kicker. We also include an Appendix where we describe a method which may further reduce the hysteresis losses of the window-frame kicker.

  14. Breaking Snake Camouflage: Humans Detect Snakes More Accurately than Other Animals under Less Discernible Visual Conditions.

    Science.gov (United States)

    Kawai, Nobuyuki; He, Hongshen

    2016-01-01

    Humans and non-human primates are extremely sensitive to snakes as exemplified by their ability to detect pictures of snakes more quickly than those of other animals. These findings are consistent with the Snake Detection Theory, which hypothesizes that as predators, snakes were a major source of evolutionary selection that favored expansion of the visual system of primates for rapid snake detection. Many snakes use camouflage to conceal themselves from both prey and their own predators, making it very challenging to detect them. If snakes have acted as a selective pressure on primate visual systems, they should be more easily detected than other animals under difficult visual conditions. Here we tested whether humans discerned images of snakes more accurately than those of non-threatening animals (e.g., birds, cats, or fish) under conditions of less perceptual information by presenting a series of degraded images with the Random Image Structure Evolution technique (interpolation of random noise). We find that participants recognize mosaic images of snakes, which were regarded as functionally equivalent to camouflage, more accurately than those of other animals under dissolved conditions. The present study supports the Snake Detection Theory by showing that humans have a visual system that accurately recognizes snakes under less discernible visual conditions.

  15. Breaking Snake Camouflage: Humans Detect Snakes More Accurately than Other Animals under Less Discernible Visual Conditions.

    Directory of Open Access Journals (Sweden)

    Nobuyuki Kawai

    Full Text Available Humans and non-human primates are extremely sensitive to snakes as exemplified by their ability to detect pictures of snakes more quickly than those of other animals. These findings are consistent with the Snake Detection Theory, which hypothesizes that as predators, snakes were a major source of evolutionary selection that favored expansion of the visual system of primates for rapid snake detection. Many snakes use camouflage to conceal themselves from both prey and their own predators, making it very challenging to detect them. If snakes have acted as a selective pressure on primate visual systems, they should be more easily detected than other animals under difficult visual conditions. Here we tested whether humans discerned images of snakes more accurately than those of non-threatening animals (e.g., birds, cats, or fish under conditions of less perceptual information by presenting a series of degraded images with the Random Image Structure Evolution technique (interpolation of random noise. We find that participants recognize mosaic images of snakes, which were regarded as functionally equivalent to camouflage, more accurately than those of other animals under dissolved conditions. The present study supports the Snake Detection Theory by showing that humans have a visual system that accurately recognizes snakes under less discernible visual conditions.

  16. Detectors for low energy electron cooling in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Carlier, F. S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-02-15

    Low-energy operation of RHIC is of particular interest to study the location of a possible critical point in the QCD phase diagram. The performance of RHIC at energies equal to or lower than 10 GV/nucleon is limited by nonlinearities, Intra-BeamScattering (IBS) processes and space-charge effects. To successfully address the luminosity and ion store lifetime limitations imposed by IBS, the method of electron cooling has been envisaged. During electron cooling processes electrons are injected along with the ion beam at the nominal ion bunch velocities. The velocity spread of the ion beam is reduced in all planes through Coulomb interactions between the cold electron beam and the ion beam. The electron cooling system proposed for RHIC will be the first of its kind to use bunched beams for the delivery of the electron bunches, and will therefore be accompanied by the necessary challenges. The designed electron cooler will be located in IP2. The electron bunches will be accelerated by a linac before being injected along side the ion beams. Thirty consecutive electron bunches will be injected to overlap with a single ion bunch. They will first cool the yellow beam before being extracted, turned by 180-degrees, and reinjected into the blue beam for cooling. As such, both the yellow and blue beams will be cooled by the same ion bunches. This will pose considerable challenges to ensure proper electron beam quality to cool the second ion beam. Furthermore, no ondulator will be used in the electron cooler so radiative recombination between the ions and the electrons will occur.

  17. The IEA Large Coil Task

    International Nuclear Information System (INIS)

    Beard, D.S.; Klose, W.; Shimamoto, S.; Vecsey, G.

    1988-01-01

    A multinational program of cooperative research, development, demonstrations, and exchanges of information on superconducting magnets for fusion was initiated in 1977 under an IEA agreement. The first major step in the development of TF magnets was called the Large Coil Task. Participants in LCT were the U.S. DOE, EURATOM, JAERI, and the Departement Federal de l'Interieur of Switzerland. The goals of LCT were to obtain experimental data, to demonstrate reliable operation of large superconducting coils, and to prove design principles and fabrication techniques being considered for the toroidal magnets of thermonuclear reactors. These goals were to be accomplished through coordinated but largely independent design, development, and construction of six test coils, followed by collaborative testing in a compact toroidal test array at fields of 8 T and higher. Under the terms of the IEA Agreement, the United States built and operated the test facility at Oak Ridge and provided three test coils. The other participants provided one coil each. Information on design and manufacturing and all test data were shared by all. The LCT team of each participant included a government laboratory and industrial partners or contractors. The last coil was completed in 1985, and the test assembly was completed in October of that year. Over the next 23 months, the six-coil array was cooled down and extensive testing was performed. Results were gratifying, as tests achieved design-point performance and well beyond. (Each coil reached a peak field of 9 T.) Experiments elucidated coil behavior, delineated limits of operability, and demonstrated coil safety. (orig./KP)

  18. Superconducting cyclotron magnet coil short

    International Nuclear Information System (INIS)

    Mallory, M.L.; Blosser, H.G.; Clark, D.J.; Launer, H.; Lawton, D.; Miller, P.; Resmini, F.

    1982-01-01

    In February 1981, a short circuit appeared in the superconducting coil of the K500 cyclotron. The short is resistive in character and therefore has no effect on steady state operation of the magnet. The resistance of the short varies, sometimes being below threshold of detection as a heat load on the cooling system and sometimes being significant. The resistance under certain conditions shows approximately cyclic phenomena with time constants in the range of seconds and other approximately cyclic phenomena which correlate with gross operating parameters of the magnet (shifting current from one coil to another at high field and lowering and raising the liquid helium level). A number of diagnostic studies of the short have been made, using 1) an array of flux sensing loops to sense the magnetic effect of the short, 2) voltage comparisons between upper and lower sections of the coil, 3) comparisons of forces in the nine member coil support system and 4) the effect of the short on the thermal charactersitics of the coil. Insulation failure or a metal chip shorting out turns have been explored in some detail but a convincing determination of the exact cause of the short may never be available, (even the extreme step of unwinding the coil having a significant probability that an imperfection with the observed characteristics would pass unnoticed). Analysis of the characteristics of the short indicated that the most serious consequence would be failure of the coils mechanical support system in the event that the magnet was quickly discharged, as in a dump or quench. To deal with this hazard, the support system has been modified by installing solid supports which prevent the coil from moving by an amount sufficient to damage the support system. We have also reexamined the data and calculations used in the original coil design and have made some additional measurements of the properties of the materials (yield strength, friction coefficient, Young's modulus) used in the

  19. DESIGN OF A FAST CHROMATICITY JUMP IN RHIC

    International Nuclear Information System (INIS)

    MONTAG, C.; KEWISCH, J.; BRUNO, D.; GANETIS, G.; LOUIE, W.

    2003-01-01

    During transition crossing in the .Relativistic Heavy Ion Collider (RHIC), chromaticities have to change sign. This sign change is partially accomplished by the γ t quadrupole jump; however, the resulting chromaticity jump is only Δξ x = 2.1 in the horizontal and Δξ y = 2.4 in the vertical plane. To increase the jump height, a dedicated chromaticity jump scheme has been designed, consisting of fast power supplies connected to six sextupoles per ring, which is capable of providing a chromaticity jump of Δξ = 6

  20. Measurement and Optimization of Local Coupling from RHIC BPM Data

    CERN Document Server

    Calaga, Rama; Bai, Mei; Fischer, Wolfram; Franchi, Andrea; Tomas, Rogelio

    2005-01-01

    Global coupling in RHIC is routinely corrected by using three skew quadrupole families to minimize the tune split. In this paper we aim to re-optimize the coupling at top energy by minimizing resonance driving terms and the C-matrix in two steps: 1. Find the best configuration of the three skew quadrupole families and 2. Identify locations with coupling sources by inspection of the driving terms and the C-matrix around the ring. The measurements of resonance terms and C-matrix are presented.

  1. Analysis of failed ramps during the RHIC FY09 run

    Energy Technology Data Exchange (ETDEWEB)

    Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-08-15

    The Relativistic Heavy Ion Collider (RHIC) is a versatile accelerator that supports operation with polarized protons of up to 250 GeV and ions with up to 100 GeV/nucleon. During any running period, various operating scenarios with different particle species, beam energies or accelerator optics are commissioned. In this report the beam commissioning periods for establishing full energy beams (ramp development periods) from the FY09 run are summarized and, for the purpose of motivating further developments, we analyze the reasons for all failed ramps.

  2. Energy Loss of Coasting Gold Ions and Deuterons in RHIC

    CERN Document Server

    Abreu, N P; Brown, K; Burkhardt, H; Butler, J; Fischer, W; Harvey, M; Tepikian, S

    2008-01-01

    The total energy loss of coasting gold ion beams at two different energies and deuterons at one energy were measured at RHIC, corresponding to a gamma of 75.2, 107.4 and 108.7 respectively. We describe the experiment and observations and compare the measured total energy loss with expectations from ionization losses at the residual gas, the energy loss due to impedance and synchrotron radiation. We find that the measured energy losses are below what is expected from free space synchrotron radiation. We believe that this shows evidence for suppression of synchrotron radiation which is cut off at long wavelength by the presence of the conducting beam pipe.

  3. Analysis of failed ramps during the RHIC FY09 run

    International Nuclear Information System (INIS)

    Minty, M.

    2014-01-01

    The Relativistic Heavy Ion Collider (RHIC) is a versatile accelerator that supports operation with polarized protons of up to 250 GeV and ions with up to 100 GeV/nucleon. During any running period, various operating scenarios with different particle species, beam energies or accelerator optics are commissioned. In this report the beam commissioning periods for establishing full energy beams (ramp development periods) from the FY09 run are summarized and, for the purpose of motivating further developments, we analyze the reasons for all failed ramps.

  4. arXiv Jet Production at RHIC and LHC

    CERN Document Server

    Cunqueiro, Leticia

    Recent results on jet production in heavy ion collisions at RHIC and the LHC are discussed, with emphasis on inclusive jet yields and semi-inclusive hadron-triggered and vector boson-triggered recoil jet yields as well as their azimuthal angular correlations. I will also discuss the constraints that these observables impose on the opacity of the medium, the flavour dependence of energy loss, the interplay of perturbative and non perturbative effects and the change of the degrees of freedom of the medium with the resolution of the probe.

  5. From the Bevalac to RHIC: Recent results and future perspectives

    International Nuclear Information System (INIS)

    Harris, J.W.

    1992-09-01

    There has been considerable theoretical progress and experimental development in the study of relativistic nucleus-nucleus collisions towards understanding the equation of state of nuclear, hadronic and partonic matter. At high energies, research has concentrated on the search for the quark-gluon plasma (QGP) and possible chiral symmetry restoration. In these lectures I comment on similarities and trends observed in recent results over a wide range of incident energies and attempt to provide a common framework where possible. I also point out future perspectives in the search for the QGP at the Relativistic Heavy Ion Collider (RHIC), and in Particular focus on one experiment to be undertaken

  6. Jets as a probe of dense matter at RHIC

    International Nuclear Information System (INIS)

    Filimonov, Kirill

    2004-01-01

    Jet quenching in the matter created in high energy nucleus-nucleus collisions provides a tomographic tool to probe the medium properties. Recent experimental results on jet production at the Relativistic Heavy-Ion Collider (RHIC) are reviewed. Jet properties in p+p and d+Au collisions have been measured, establishing the baseline for studying jet modification in heavy-ion collisions. Current progress on detailed studies of high transverse momentum production in Au+Au collisions is discussed, with an emphasis on dihadron correlation measurements

  7. Statistical error of spin transfer to hyperon at RHIC energy

    International Nuclear Information System (INIS)

    Han Ran; Mao Yajun

    2009-01-01

    From the RHIC/PHENIX experiment data, it is found that the statistical error of spin transfer is few times larger than the statistical error of the single spin asymmetry. In order to verify the difference between σDLL and σAL, the linear least squares method was used to check it first, and then a simple Monte-Carlo simulation to test this factor again. The simulation is consistent with the calculation result which indicates that the few times difference is reasonable. (authors)

  8. Phenomenology of the squeezed hadronic correlations at RHIC energies

    International Nuclear Information System (INIS)

    Padula, Sandra S.; Dudek, Danuce M.; Socolowski, Otavio Jr.

    2012-01-01

    We briefly review the basic theoretical results on bosonic back-to-back correlations (bBBC) and compare our predictions with the first experimental search for squeezed correlations of K + K - pairs, performed by PHENIX. The hadronic squeezed correlations are very sensitive to the functional form of the time emission distribution. The comparison is made for three different kaon time distributions. From such comparison we show that the outcome of the experimental search may still be inconclusive but it does not exclude the existence of squeezing effects on hadrons with in-medium modified masses already at RHIC energies. (author)

  9. Construction details and test results from RHIC sextupoles

    International Nuclear Information System (INIS)

    Lindner, M.; Anerella, M.; Ganetis, G.

    1993-01-01

    Four 8 cm aperture sextupoles have been built at BNL to verify the magnetic performance of this magnet in the RHIC installation. Two significantly different mechanical configurations have been designed, and two magnets of each design have been built, and successfully tested, and have exceeded the required minimum quench current by a substantial margin. This report describes the assembly details of the second configuration, which is the final production configuration. In addition the first industry built production sextupole has been delivered and tested. This report presents the results of quench tests on all 5 magnets and field measurements on the first production sextupole

  10. Design and test of the RHIC CMD10 abort kicker

    International Nuclear Information System (INIS)

    Hahn, H.; Blaskiewicz, M.; Drees, A.; Fischer, W.; Mi, J.; Meng, W.; Montag, C.; Pai, C.; Sandberg, J.; Tsoupas, N.; Tuozzolo, J. E.; Zhang, W.

    2015-01-01

    In recent RHIC operational runs, planned and unplanned pre-fire triggered beam aborts have been observed that resulted in quenches of SC main ring magnets, indicating a weakened magnet kick strength due to beam-induced ferrite heating. An improvement program was initiated to reduce the longitudinal coupling impedance with changes to the ferrite material and the eddy-current strip geometry. Results of the impedance measurements and of magnet heating tests with CMD10 ferrite up to 190°C are reported. All 10 abort kickers in the tunnel have been modified and were provided with a cooling system for the RUN 15.

  11. Simulation of jet quenching at RHIC and LHC

    International Nuclear Information System (INIS)

    Lokhtin, I P; Snigirev, A M

    2007-01-01

    A model to simulate the jet quenching effect in ultrarelativistic heavy ion collisions is presented. The model is the fast Monte Carlo tool implemented to modify a standard PYTHIA jet event. The model has been generalized to the case of the 'full' heavy ion event (the superposition of soft, hydro-type state and hard multi-jets) using a simple and fast simulation procedure for soft particle production. The model is capable of reproducing the main features of the jet quenching pattern at RHIC and is applied to analyse novel jet quenching features at LHC

  12. Direct Photons and Dileptons in PHENIX at RHIC

    International Nuclear Information System (INIS)

    David, G.

    2009-01-01

    Direct photons and dileptons are penetrating probes of relativistic heavy ion collisions. Generated throughout the entire history of the collision and then emerging without further interaction they give insight into basic processes that are otherwise not directly accessible experimentally. One of the main objectives and strengths of the PHENIX experiment at RHIC is the measurement of both types of electromagnetic probes in the same apparatus and in the widest p T range in nucleon-nucleon and heavy ion collisions. The experimental results and recent developments of theory started to change our perception of high transverse momentum photons from A+A collisions.

  13. Elliptic flow in Au+Au collisions at RHIC

    Science.gov (United States)

    Vale, Carla M.; PHOBOS Collaboration; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; García, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Holynski, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Ngyuen, M.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tang, J.-L.; Tonjes, M. B.; Trzupek, A.; van Nieuwenhuizen, G. J.; Verdier, R.; Veres, G.; Wolfs, F. L. H.; Wosiek, B.; Wozniak, K.; Wuosmaa, A. H.; Wyslouch, B.

    2005-04-01

    Elliptic flow is an interesting probe of the dynamical evolution of the dense system formed in the ultrarelativistic heavy ion collisions at the relativistic heavy ion collider (RHIC). The elliptic flow dependences on transverse momentum, centrality and pseudorapidity were measured using data collected by the PHOBOS detector, which offers a unique opportunity to study the azimuthal anisotropies of charged particles over a wide range of pseudorapidity. These measurements are presented, together with an overview of the analysis methods and a discussion of the results.

  14. RESONANT BPM FOR CONTINUOUS TUNE MEASUREMENT IN RHIC

    International Nuclear Information System (INIS)

    KESSELMAN, M.; CAMERON, P.; CUPOLO, J.

    2001-01-01

    A movable Beam Position Monitor (BPM) using shorted stripline Pick-Up Electrode (NE) elements has been resonated using matching stub techniques to achieve a relatively high Q resonance at about 230MHz. This PUE has been used in a feasibility study of phase-locked-loop tune measurement [1], using a lock-in amplifier and variable frequency generator to continuously track betatron tune in RHIC, as well as to observe Schottky signals of the Gold beam. The approach to providing a high Q PUE for difference mode signals, simulation studies, and the results of initial tests will be presented

  15. Superconducting poloidal coils for STARFIRE commercial reactor

    International Nuclear Information System (INIS)

    Wang, S.T.; Evans, K. Jr.; Turner, L.R.; Huang, Y.C.; Prater, R.; Alcorn, J.

    1979-01-01

    STARFIRE is considered to be the tenth commercial tokamak power plant. A preliminary design study on its superconducting poloidal coil system is presented. Key features of the design studies are: the elimination of the ohmic heating coil; the trade-off studies of the equilibrium field coil locations; and the development of a conceptual design for the superconducting equilibrium field coils. Described are the 100 kA cryostable conductor design, the coil structure, and evaluation of the coil forces

  16. 33 CFR 117.385 - Snake River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Snake River. 117.385 Section 117.385 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Idaho § 117.385 Snake River. The drawspan of the U.S. 12 bridge...

  17. An unusual complication of snake bite

    Directory of Open Access Journals (Sweden)

    Mary Grace

    2014-01-01

    Full Text Available Anterior pituitary hypofunction is a well-known complication following snake bite. However, central diabetes insipidus as a complication of snake bite is only rarely reported in the literature. We are reporting a case of central diabetes insipidus, which developed as sequelae to viper bite.

  18. On a collection of Snakes from Dehli

    NARCIS (Netherlands)

    Lidth de Jeude, van Th.W.

    1890-01-01

    During his stay in Laboean (Delili, East-Sumatra) Dr. B. Hagen, to whom the Leyden Museum is indebted for large series of mammals, birds and insects, also collected a large number of snakes, the greater part of which were sent to our Museum. Dr. Hagen took a lively interest in snakes, and being

  19. Evolutionary stability of sex chromosomes in snakes.

    Science.gov (United States)

    Rovatsos, Michail; Vukić, Jasna; Lymberakis, Petros; Kratochvíl, Lukáš

    2015-12-22

    Amniote vertebrates possess various mechanisms of sex determination, but their variability is not equally distributed. The large evolutionary stability of sex chromosomes in viviparous mammals and birds was believed to be connected with their endothermy. However, some ectotherm lineages seem to be comparably conserved in sex determination, but previously there was a lack of molecular evidence to confirm this. Here, we document a stability of sex chromosomes in advanced snakes based on the testing of Z-specificity of genes using quantitative PCR (qPCR) across 37 snake species (our qPCR technique is suitable for molecular sexing in potentially all advanced snakes). We discovered that at least part of sex chromosomes is homologous across all families of caenophidian snakes (Acrochordidae, Xenodermatidae, Pareatidae, Viperidae, Homalopsidae, Colubridae, Elapidae and Lamprophiidae). The emergence of differentiated sex chromosomes can be dated back to about 60 Ma and preceded the extensive diversification of advanced snakes, the group with more than 3000 species. The Z-specific genes of caenophidian snakes are (pseudo)autosomal in the members of the snake families Pythonidae, Xenopeltidae, Boidae, Erycidae and Sanziniidae, as well as in outgroups with differentiated sex chromosomes such as monitor lizards, iguanas and chameleons. Along with iguanas, advanced snakes are therefore another example of ectothermic amniotes with a long-term stability of sex chromosomes comparable with endotherms. © 2015 The Author(s).

  20. Snake venom instability | Willemse | African Zoology

    African Journals Online (AJOL)

    Egyptian cobra Naja haje haje) and puffadder (Bills arietans). Considerable differences in electrophoretic characteristics were found between fresh venom and commercial venom samples from the same species of snake. These differences could be attributed partly to the instability of snake venom under conditions of drying ...

  1. Snake Genome Sequencing: Results and Future Prospects.

    Science.gov (United States)

    Kerkkamp, Harald M I; Kini, R Manjunatha; Pospelov, Alexey S; Vonk, Freek J; Henkel, Christiaan V; Richardson, Michael K

    2016-12-01

    Snake genome sequencing is in its infancy-very much behind the progress made in sequencing the genomes of humans, model organisms and pathogens relevant to biomedical research, and agricultural species. We provide here an overview of some of the snake genome projects in progress, and discuss the biological findings, with special emphasis on toxinology, from the small number of draft snake genomes already published. We discuss the future of snake genomics, pointing out that new sequencing technologies will help overcome the problem of repetitive sequences in assembling snake genomes. Genome sequences are also likely to be valuable in examining the clustering of toxin genes on the chromosomes, in designing recombinant antivenoms and in studying the epigenetic regulation of toxin gene expression.

  2. Snake Genome Sequencing: Results and Future Prospects

    Directory of Open Access Journals (Sweden)

    Harald M. I. Kerkkamp

    2016-12-01

    Full Text Available Snake genome sequencing is in its infancy—very much behind the progress made in sequencing the genomes of humans, model organisms and pathogens relevant to biomedical research, and agricultural species. We provide here an overview of some of the snake genome projects in progress, and discuss the biological findings, with special emphasis on toxinology, from the small number of draft snake genomes already published. We discuss the future of snake genomics, pointing out that new sequencing technologies will help overcome the problem of repetitive sequences in assembling snake genomes. Genome sequences are also likely to be valuable in examining the clustering of toxin genes on the chromosomes, in designing recombinant antivenoms and in studying the epigenetic regulation of toxin gene expression.

  3. 27 CFR 9.208 - Snake River Valley.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Snake River Valley. 9.208... Snake River Valley. (a) Name. The name of the viticultural area described in this section is “Snake River Valley”. For purposes of part 4 of this chapter, “Snake River Valley” is a term of viticultural...

  4. 77 FR 10960 - Drawbridge Operation Regulation; Snake Creek, Islamorada, FL

    Science.gov (United States)

    2012-02-24

    ... Operation Regulation; Snake Creek, Islamorada, FL AGENCY: Coast Guard, DHS. ACTION: Notice of temporary... deviation from the regulation governing the operation of Snake Creek Bridge, mile 0.5, across Snake Creek... schedule of Snake Creek Bridge in Islamorada, Florida. This deviation will result in the bridge opening...

  5. Epidemiology of Snake Bites among Selected Communities in the ...

    African Journals Online (AJOL)

    Snake is one of the major group of games feared by people in many localities because of their venoms, yet snakes are equally afraid of human beings. This balance of terror apart from affecting both man and snakes has also led to their deaths. Epidemiology of snake bites among selected communities in the enclave of ...

  6. Coil protection calculator for TFTR

    International Nuclear Information System (INIS)

    Marsala, R.J.; Lawson, J.E.; Persing, R.G.; Senko, T.R.; Woolley, R.D.

    1989-01-01

    A new coil protection system (CPS) is being developed to replace the existing TFTR magnetic coil fault detector. The existing fault detector sacrifices TFTR operating capability for simplicity. The new CPS, when installed in October of 1988, will permit operation up to the actual coil stress limits parameters in real-time. The computation will be done in a microprocessor based Coil Protection Calculator (CPC) currently under construction at PPL. THe new CPC will allow TFTR to operate with higher plasma currents and will permit the optimization of pulse repetition rates. The CPC will provide real-time estimates of critical coil and bus temperatures and stresses based on real-time redundant measurements of coil currents, coil cooling water inlet temperature, and plasma current. The critical parameter calculations are compared to prespecified limits. If these limits are reached or exceeded, protection action will be initiated to a hard wired control system (HCS), which will shut down the power supplies. The CPC consists of a redundant VME based microprocessor system which will sample all input data and compute all stress quantities every ten milliseconds. Thermal calculations will be approximated every 10ms with an exact solution occurring every second. The CPC features continuous cross-checking of redundant input signal, automatic detection of internal failure modes, monitoring and recording of calculated results, and a quick, functional verification of performance via an internal test system. (author)

  7. Can doubly strange dibaryon resonances be discovered at RHIC?

    International Nuclear Information System (INIS)

    Paganis, S. D.; Hoffmann, G. W.; Ray, R. L.; Tang, J.-L.; Udagawa, T.; Longacre, R. S.

    2000-01-01

    The baryon-baryon continuum invariant mass spectrum generated from relativistic nucleus + nucleus collision data may reveal the existence of doubly strange dibaryons not stable against strong decay if they lie within a few MeV of threshold. Furthermore, since the dominant component of these states is a superposition of two color-octet clusters which can be produced intermediately in a color-deconfined quark-gluon plasma (QGP), an enhanced production of dibaryon resonances could be a signal of QGP formation. A total of eight, doubly strange dibaryon states are considered for experimental search using the STAR detector (solenoidal tracker at RHIC) at the new Relativistic Heavy Ion Collider (RHIC). These states may decay to ΛΛ and/or pΞ - , depending on the resonance energy. STAR's large acceptance, precision tracking and vertex reconstruction capabilities, and large data volume capacity, make it an ideal instrument to use for such a search. Detector performance and analysis sensitivity are studied as a function of resonance production rate and width for one particular dibaryon which can directly strong decay to pΞ - , but not ΛΛ. Results indicate that such resonances may be discovered using STAR if the resonance production rates are comparable to coalescence model predictions for dibaryon bound states. (c) 2000 The American Physical Society

  8. Conceptual design of the Relativistic Heavy Ion Collider: RHIC

    International Nuclear Information System (INIS)

    1986-05-01

    The complete Relativistic Heavy Ion Collider (RHIC) facility will be a complex set of accelerators and beam transfer equipment connecting them. A significant portion of the total facility either exists or is under construction. Two existing Tandem Van de Graaff accelerators will serve for the initial ion acceleration. Ions with a charge of -1 would be accelerated from ground to +15 MV potential, pass through a stripping foil, and accelerate back to ground potential, where they would pass through a second stripping foil. From there the ions will traverse a long transfer line to the AGS tunnel and be injected into the Booster accelerator. The Booster accelerates the ion bunch, and then the ions pass through one more stripper and then enter the Alternating Gradient Synchrotron (AGS), where they are accelerated to the top AGS energy and transferred to the collider. Bending and focusing of ion beams is to be achieved by superconducting magnets. The physics goals behind the RHIC are enumerated, particularly as regards the study of quark matter and the characteristics of high energy nucleus-nucleus collisions. The design of the collider and all its components is described, including the injector, the lattice, magnet system, cryogenic and vacuum systems, beam transfer, injection, and dump, rf system, and beam instrumentation and control system. Also given are cost estimates, construction schedules, and a management plan

  9. The gold flashlight: Coherent photons (and Pomerons) at RHIC

    International Nuclear Information System (INIS)

    Klein, S.; Scannapieco, E.

    1997-06-01

    The Relativistic Heavy Ion Collider (RHIC) will be the first heavy ion accelerator energetic enough to produce hadronic final states via coherent γγ, γP, and PP interactions. Because the photon flux scales as Z 2 , up to an energy of about γℎc/R ∼ 3 GeV/c, the γγ interaction rates are large. RHIC γP interactions test how Pomerons couple to nuclei and measure how different vector mesons, including the J/ψ, interact with nuclear matter. PP collisions can probe Pomeron couplings. Because these collisions can involve identical initial states, for identical final states, the γγ, γP, and PP channels may interfere, producing new effects. The authors review the physics of these interactions and discuss how these signals can be detected experimentally, in the context of the STAR detector. Signals can be separated from backgrounds by using isolation cuts (rapidity gaps) and p perpendicular. The authors present Monte Carlo studies of different backgrounds, showing that representative signals can be extracted with good rates and signal to noise ratios

  10. RAPIDE 0.0 RHIC Accelerator Physics Intrepid Development Environment

    Energy Technology Data Exchange (ETDEWEB)

    Satogata, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Saltmarsh, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Peggs, S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    1993-08-01

    This document is a guide to the common environmental features of computing in (and around) the RHIC Accelerator Physics.sectio on the 'zoo' cluster of UNJX workstations, in RAPIDE, the RHIC Accelerator Physics Intrepid Development Environment It is hoped tliat later revisions of this document will approach a more professional 'style guide', beyond the convenient collection of pointers and hints presented here. RAP does two kinds of computing, "controls" and "general", addressed in sections 2 and 3 of this document For general computing, efficient system administration requires cooperation in using a common environment There is a much stronger need to define - and adhere to - a commonly agreed set of styles (or rules) in developing controls software. Right now, these rules have been set "de facto". Future improvements to the controls environment, particularly in response to the opinions of users, depends on broad knowledge of what the rules are. There are environmental issues that are basic to both controls and general computing, and that are so fundamental that they are (almost) unarguable. They are described immediately below, in the next section.

  11. The strongly coupled quark-gluon plasma created at RHIC

    International Nuclear Information System (INIS)

    Heinz, Ulrich

    2009-01-01

    The relativistic heavy-ion collider (RHIC) was built to re-create and study in the laboratory the extremely hot and dense matter that filled our entire universe during its first few microseconds. Its operation since June 2000 has been extremely successful, and the four large RHIC experiments have produced an impressive body of data which indeed provide compelling evidence for the formation of thermally equilibrated matter at unprecedented temperatures and energy densities-a 'quark-gluon plasma (QGP)'. A surprise has been the discovery that this plasma behaves like an almost perfect fluid, with extremely low viscosity. Theorists had expected a weakly interacting gas of quarks and gluons, but instead we seem to have created a strongly coupled plasma liquid. The experimental evidence strongly relies on a feature called 'elliptic flow' in off-central collisions, with additional support from other observations. This paper explains how we probe the strongly coupled QGP, describes the ideas and measurements which led to the conclusion that the QGP is an almost perfect liquid, and shows how they tie relativistic heavy-ion physics into other burgeoning fields of modern physics, such as strongly coupled Coulomb plasmas, ultracold systems of trapped atoms and superstring theory

  12. Highlights from PHENIX transverse spin program at RHIC

    International Nuclear Information System (INIS)

    Liu, M.

    2013-01-01

    In recent years, there has been exciting development in both experimental and theoretical studies of transverse spin phenomena in high energy polarized p+p and polarized DIS collisions. In the p+p frontier, the polarized p+p collider at RHIC provides a unique opportunity to investigate the novel physics that causes the large spin effects seen in the transversely polarized p+p collisions over the past 30 years, particularly in the forward rapidity. Since the beginning, PHENIX has been conducting a very active transverse spin physics program to study Sivers, Collins and other novel spin effects at RHIC, including measurements of transverse single spin asymmetry (TSSA) in light and heavy quark productions, leading neutron TSSA in the very forward rapidity, and di-hadron (and 'jet') spin correlations in a wide kinematics range, just to name a few. In 2012, PHENIX collected transversely polarized 200 GeV p+p data with a record high luminosity of 9.24 pb −1 , with an average beam polarization of 58%. In this talk, I highlight the recent results from the PHENIX experiment, and also briefly discuss the near-term prospects of new transverse spin measurements only possible with the latest (forward) silicon vertex detectors, (F)VTX, and the upcoming forward MPC-EX upgrade detectors.

  13. Sea Snake Harvest in the Gulf of Thailand

    DEFF Research Database (Denmark)

    Van Cao, Nguyen; Thien Tao, Nguyen; Moore, Amelia

    2014-01-01

    Abstract: Conservation of sea snakes is virtually nonexistent in Asia, and its role in human–snake interactions in terms of catch, trade, and snakebites as an occupational hazard is mostly unexplored. We collected data on sea snake landings from the Gulf of Thailand, a hotspot for sea snake harvest...... years), and the treatment of sea snake bites with rhinoceros horn. Emerging markets in Southeast Asia drive the harvest of venomous sea snakes in the Gulf of Thailand and sea snake bites present a potentially lethal occupational hazard. We call for implementation of monitoring programs to further...... address the conservation implications of this large-scale marine reptile exploitation....

  14. Exploring a possible origin of a 14 deg y-normal spin tilt at RHIC polarimeter

    Energy Technology Data Exchange (ETDEWEB)

    Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-06-15

    A possible origin of a 14 deg y-normal spin n0 tilt at the polarimeter is in snake angle defects. This possible cause is investigated by scanning the snake axis angle µ, and the spin rotation angle at the snake, φ, in the vicinity of their nominal values.

  15. Exponential asymptotics of homoclinic snaking

    International Nuclear Information System (INIS)

    Dean, A D; Matthews, P C; Cox, S M; King, J R

    2011-01-01

    We study homoclinic snaking in the cubic-quintic Swift–Hohenberg equation (SHE) close to the onset of a subcritical pattern-forming instability. Application of the usual multiple-scales method produces a leading-order stationary front solution, connecting the trivial solution to the patterned state. A localized pattern may therefore be constructed by matching between two distant fronts placed back-to-back. However, the asymptotic expansion of the front is divergent, and hence should be truncated. By truncating optimally, such that the resultant remainder is exponentially small, an exponentially small parameter range is derived within which stationary fronts exist. This is shown to be a direct result of the 'locking' between the phase of the underlying pattern and its slowly varying envelope. The locking mechanism remains unobservable at any algebraic order, and can only be derived by explicitly considering beyond-all-orders effects in the tail of the asymptotic expansion, following the method of Kozyreff and Chapman as applied to the quadratic-cubic SHE (Chapman and Kozyreff 2009 Physica D 238 319–54, Kozyreff and Chapman 2006 Phys. Rev. Lett. 97 44502). Exponentially small, but exponentially growing, contributions appear in the tail of the expansion, which must be included when constructing localized patterns in order to reproduce the full snaking diagram. Implicit within the bifurcation equations is an analytical formula for the width of the snaking region. Due to the linear nature of the beyond-all-orders calculation, the bifurcation equations contain an analytically indeterminable constant, estimated in the previous work by Chapman and Kozyreff using a best fit approximation. A more accurate estimate of the equivalent constant in the cubic-quintic case is calculated from the iteration of a recurrence relation, and the subsequent analytical bifurcation diagram compared with numerical simulations, with good agreement

  16. 50 CFR Table 3 to Part 226 - Hydrologic Units Containing Critical Habitat for Snake River Sockeye Salmon and Snake River...

    Science.gov (United States)

    2010-10-01

    ... Habitat for Snake River Sockeye Salmon and Snake River Spring/Summer and Fall Chinook Salmon 3 Table 3 to... Part 226—Hydrologic Units Containing Critical Habitat for Snake River Sockeye Salmon and Snake River... Snake—Asotin 17060103 17060103 17060103 Upper Grande Ronde 17060104 Wallowa 17060105 Lower Grande Ronde...

  17. A 4.7 tesla metre solenoid for a partial Siberian snake

    International Nuclear Information System (INIS)

    Ratner, L.; Leonhardt, W.; Otter, A.; Ellstrom, L.

    1993-11-01

    We describe the engineering design of a 4.7 T-m solenoid magnet which will be installed at the Brookhaven National Laboratory AGS for a partial Siberian Snake Experiment which is an interlaboratory collaboration. The magnet has an overall length of 2.5 m, a clear bore of 15 cm and operates at a peak field of 2 T. It is pulsed at 3 second intervals with a peak current of 9500 A dc driven from a 150 V power supply. The construction uses conventional hollow copper coils but the return flux yokes are made from 1/8 inch plates bolted together. On assembly the flux yokes and endplates are clamped tightly to the coil to prevent any movement during the current pulse. The fabrication experience and test data will be presented. The magnet was installed in the summer of 1993. (author). 3 refs., 1 tab., 1 fig

  18. A 4.7 tesla metre solenoid for a partial Siberian snake

    Energy Technology Data Exchange (ETDEWEB)

    Ratner, L; Leonhardt, W [Brookhaven National Lab., Upton, NY (United States); Otter, A; Ellstrom, L

    1993-11-01

    We describe the engineering design of a 4.7 T-m solenoid magnet which will be installed at the Brookhaven National Laboratory AGS for a partial Siberian Snake Experiment which is an interlaboratory collaboration. The magnet has an overall length of 2.5 m, a clear bore of 15 cm and operates at a peak field of 2 T. It is pulsed at 3 second intervals with a peak current of 9500 A dc driven from a 150 V power supply. The construction uses conventional hollow copper coils but the return flux yokes are made from 1/8 inch plates bolted together. On assembly the flux yokes and endplates are clamped tightly to the coil to prevent any movement during the current pulse. The fabrication experience and test data will be presented. The magnet was installed in the summer of 1993. (author). 3 refs., 1 tab., 1 fig.

  19. Coil for LEAR extraction septum

    CERN Multimedia

    CERN PhotoLab

    1982-01-01

    Which way does the current flow ? This intriguing object is the coil for the LEAR extraction septum. There were two septa, first a thin one, then this one, not so thin, somewhat on the borderline between septum and bending magnet.

  20. First coil for the SC

    CERN Multimedia

    CERN PhotoLab

    1955-01-01

    The coils for the SC magnet were stored in the large hangar of the Cointrin Airport (to make sure that they would be available before snow and ice would block the roads and canals from Belgium, where they were built).

  1. The effects of betatron phase advances on beam-beam and its compensation in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Y.; Fischer, W.; Gu, X.; Tepikian, S.; Trbojevic, D.

    2011-03-28

    In this article we perform simulation studies to investigate the effects of betatron phase advances between the beam-beam interaction points on half-integer resonance driving term, second order chromaticty and dynamic aperture in RHIC. The betatron phase advances are adjusted with artificial matrices inserted in the middle of arcs. The lattices for the 2011 RHIC polarized proton (p-p) run and 2010 RHIC Au-Au runs are used in this study. We also scan the betatron phase advances between IP8 and the electron lens for the proposed Blue ring lattice with head-on beam-beam compensation.

  2. THE COUPLING CORRECTION SYSTEM AT RHIC: RESULTS FOR THE RUN 2000 AND PLANS FOR 2001

    International Nuclear Information System (INIS)

    Pilat, F.; Fischer, W.; Peggs, S.; Ptitsyn, V.; Tepikian, S.

    2001-01-01

    The RHIC coupling correction system has been commissioned during the Year 2000 run, which marked the successful first year of operation of the machine. The RHIC coupling correction system is described with particular emphasis on its flexibility, which allows using both global and local coupling compensation techniques. Coupling measurements and correction data are presented for the RHIC Blue and Yellow rings, together with the procedure used to reduce the minimum tune separation to 0.001, the typical resolution for tune measurements during run 2000. They further demonstrate how local coupling compensation in the interaction region substantially reduces the strength of the skew quadrupole families used for global coupling compensation

  3. Radiation resistant ducted superconductive coil

    International Nuclear Information System (INIS)

    Schleich, A.

    1976-01-01

    The radiation-resistant ducted superconductive coil consists of a helically wound electrical conductor constituted by an electrically conductive core of superconductive material provided with a longitudinally extending cooling duct. The core is covered with a layer of inorganic insulating material and the duct is covered by an electrically conductive metallic gas-tight sheath. The metallic sheaths on adjacent turns of the coil are secured together. 2 Claims, 4 Drawing Figures

  4. The Swiss LCT-coil

    International Nuclear Information System (INIS)

    Vecsey, G.; Benz, H.; Horvath, I.

    1985-01-01

    With delivery of the coil to ORNL on February 4, 1984, the second phase of the Swiss Large Coil Program - design and construction - was terminated. Mainlines of the Swiss design concept are summarized and related to theoretical calculations, experimental results of the supporting program, fabricational experience and first successful test results. An attempt is made to draw preliminary conclusions with regard to the design of future toroidal systems such as NET

  5. Computational Studies of Snake Venom Toxins.

    Science.gov (United States)

    Ojeda, Paola G; Ramírez, David; Alzate-Morales, Jans; Caballero, Julio; Kaas, Quentin; González, Wendy

    2017-12-22

    Most snake venom toxins are proteins, and participate to envenomation through a diverse array of bioactivities, such as bleeding, inflammation, and pain, cytotoxic, cardiotoxic or neurotoxic effects. The venom of a single snake species contains hundreds of toxins, and the venoms of the 725 species of venomous snakes represent a large pool of potentially bioactive proteins. Despite considerable discovery efforts, most of the snake venom toxins are still uncharacterized. Modern bioinformatics tools have been recently developed to mine snake venoms, helping focus experimental research on the most potentially interesting toxins. Some computational techniques predict toxin molecular targets, and the binding mode to these targets. This review gives an overview of current knowledge on the ~2200 sequences, and more than 400 three-dimensional structures of snake toxins deposited in public repositories, as well as of molecular modeling studies of the interaction between these toxins and their molecular targets. We also describe how modern bioinformatics have been used to study the snake venom protein phospholipase A2, the small basic myotoxin Crotamine, and the three-finger peptide Mambalgin.

  6. Computational Studies of Snake Venom Toxins

    Directory of Open Access Journals (Sweden)

    Paola G. Ojeda

    2017-12-01

    Full Text Available Most snake venom toxins are proteins, and participate to envenomation through a diverse array of bioactivities, such as bleeding, inflammation, and pain, cytotoxic, cardiotoxic or neurotoxic effects. The venom of a single snake species contains hundreds of toxins, and the venoms of the 725 species of venomous snakes represent a large pool of potentially bioactive proteins. Despite considerable discovery efforts, most of the snake venom toxins are still uncharacterized. Modern bioinformatics tools have been recently developed to mine snake venoms, helping focus experimental research on the most potentially interesting toxins. Some computational techniques predict toxin molecular targets, and the binding mode to these targets. This review gives an overview of current knowledge on the ~2200 sequences, and more than 400 three-dimensional structures of snake toxins deposited in public repositories, as well as of molecular modeling studies of the interaction between these toxins and their molecular targets. We also describe how modern bioinformatics have been used to study the snake venom protein phospholipase A2, the small basic myotoxin Crotamine, and the three-finger peptide Mambalgin.

  7. The SMES model coil. Fabrication

    International Nuclear Information System (INIS)

    Hanai, Satoshi; Nakamoto, Kazunari; Takahashi, Nobuji

    1998-01-01

    A SMES model coil was fabricated as R and D item in the development of component technologies for a 480 MJ/20 MW SMES pilot plant. The coil consists of four double-pancake windings. The coil is the same diameter but half the number of pancakes that will be needed for a SMES pilot plant. The NbTi cable-in-conduit conductor and superconducting joints between the double pancakes are cooled by a forced flow of supercritical helium. Prior to fabrication, various characteristics of the cable-in-conduit were measured by full-sized short samples from actual conductors and by scaled short samples from scaled conductors. The critical current of the scaled short samples was in agreement with that calculated from one strand of the conductor. The impedance between arbitrary dual-oxide coated strands in the full-size conductor was measured to be smaller than that obtained from two Cr-plated strands, which showed a good degree of stability in another coil. It was estimated that oxide-coated conductors would have high stability. Through fabrication of a model coil, it was demonstrated that a large forced-flow coil for a small-scale 100 kWh SMES device could be manufactured. (author)

  8. The SMES model coil. Fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Hanai, Satoshi; Nakamoto, Kazunari; Takahashi, Nobuji [Toshiba Corp., Yokohama, Kanagawa (Japan)] [and others

    1998-07-01

    A SMES model coil was fabricated as R and D item in the development of component technologies for a 480 MJ/20 MW SMES pilot plant. The coil consists of four double-pancake windings. The coil is the same diameter but half the number of pancakes that will be needed for a SMES pilot plant. The NbTi cable-in-conduit conductor and superconducting joints between the double pancakes are cooled by a forced flow of supercritical helium. Prior to fabrication, various characteristics of the cable-in-conduit were measured by full-sized short samples from actual conductors and by scaled short samples from scaled conductors. The critical current of the scaled short samples was in agreement with that calculated from one strand of the conductor. The impedance between arbitrary dual-oxide coated strands in the full-size conductor was measured to be smaller than that obtained from two Cr-plated strands, which showed a good degree of stability in another coil. It was estimated that oxide-coated conductors would have high stability. Through fabrication of a model coil, it was demonstrated that a large forced-flow coil for a small-scale 100 kWh SMES device could be manufactured. (author)

  9. Equilibrium field coil concepts for INTOR

    International Nuclear Information System (INIS)

    Strickler, D.J.; Peng, Y.K.M.; Brown, T.G.

    1981-08-01

    Methods are presented for reducing ampere-turn requirements in the EF coil system. It is shown that coil currents in an EF coil system external to the toroidal field coils can be substantially reduced by relaxing the triangularity of a D-shaped plasma. Further reductions are realized through a hybrid EF coil system using both internal and external coils. Equilibrium field coils for a poloidally asymmetric, single-null INTOR configuration are presented. It is shown that the shape of field lines in the plasma scrapeoff region and divertor channel improves as triangularity is reduced, but it does so at the possible expense of achievable stable beta values

  10. High-energy high-luminosity electron-ion collider eRHIC

    International Nuclear Information System (INIS)

    Litvinenko, V.N.; Ben-Zvi, I.; Hammons, L.; Hao, Y.; Webb, S.

    2011-01-01

    In this paper, we describe a future electron-ion collider (EIC), based on the existing Relativistic Heavy Ion Collider (RHIC) hadron facility, with two intersecting superconducting rings, each 3.8 km in circumference. The replacement cost of the RHIC facility is about two billion US dollars, and the eRHIC will fully take advantage and utilize this investment. We plan adding a polarized 5-30 GeV electron beam to collide with variety of species in the existing RHIC accelerator complex, from polarized protons with a top energy of 325 GeV, to heavy fully-striped ions with energies up to 130 GeV/u. Brookhaven's innovative design, is based on one of the RHIC's hadron rings and a multi-pass energy-recovery linac (ERL). Using the ERL as the electron accelerator assures high luminosity in the 10 33 -10 34 cm -2 sec -1 range, and for the natural staging of eRHIC, with the ERL located inside the RHIC tunnel. The eRHIC will provide electron-hadron collisions in up to three interaction regions. We detail the eRHIC's performance in Section 2. Since first paper on eRHIC paper in 2000, its design underwent several iterations. Initially, the main eRHIC option (the so-called ring-ring, RR, design) was based on an electron ring, with the linac-ring (LR) option as a backup. In 2004, we published the detailed 'eRHIC 0th Order Design Report' including a cost-estimate for the RR design. After detailed studies, we found that an LR eRHIC has about a 10-fold higher luminosity than the RR. Since 2007, the LR, with its natural staging strategy and full transparency for polarized electrons, became the main choice for eRHIC. In 2009, we completed technical studies of the design and dynamics for MeRHIC with 3-pass 4 GeV ERL. We learned much from this evaluation, completed a bottom-up cost estimate for this $350M machine, but then shelved the design. In the same year, we turned again to considering the cost-effective, all-in-tunnel six-pass ERL for our design of the high-luminosity eRHIC. In it

  11. Design and analysis of coiled fiber reinforced soft pneumatic actuator.

    Science.gov (United States)

    Singh, Gaurav; Xiao, Chenzhang; Hsiao-Wecksler, Elizabeth T; Krishnan, Girish

    2018-04-18

    Fiber reinforced elastomeric enclosures (FREEs) are soft pneumatic actuators that can contract and generate forces upon pressurization. Typical engineering applications utilize FREEs in their straight cylindrical configuration and derive actuation displacement and forces from their ends. However, there are several instances in nature, such as an elephant trunk, snakes and grapevine tendrils, where a spiral configuration of muscle systems is used for gripping, thereby establishing a mechanical connection with uniform force distribution. Inspired by these examples, this paper investigates the constricting behavior of a contracting FREE actuator deployed in a spiral or coiled configuration around a cylindrical object. Force balance is used to model the blocked force of the FREE, which is then related to the constriction force using a string model. The modeling and experimental findings reveal an attenuation in the blocked force, and thus the constriction force caused by the coupling of peripheral contact forces acting in the spiral configuration. The usefulness of the coiled FREE configuration is demonstrated in a soft arm orthosis for crutch users that provides a constriction force around the forearm. This design minimizes injury risk by reducing wrist load and improving wrist posture.

  12. Endovascular rescue method for undesirably stretched coil.

    Science.gov (United States)

    Cho, Jae Hoon

    2014-10-01

    Undesirable detachment or stretching of coils within the parent artery during aneurysm embolization can be related with thrombus formation, which can be caused occlusion of parent artery or embolic event(s). To escape from this situation, several rescue methods have been reported. A case with undesirably stretched coil in which another rescue method was used, is presented. When the stretched coil is still located in the coil delivery microcatheter, the stretched coil can be removed safely using a snare and a handmade monorail microcatheter. After a snare is lodged in the handmade monorail microcatheter, the snare is introduced over the coil delivery micorcatheter and located in the distal part of the stretched coil. After then, the handmade monorail microcatheter captures the stretched coil and the snare as one unit. This technique using a handmade monorail microcatheter and a snare can be a good rescue modality for the undesirably stretched coil, still remained within the coil delivery microcatheter.

  13. North American snake and scorpion envenomations.

    Science.gov (United States)

    Wilbeck, Jennifer; Gresham, Chip

    2013-06-01

    Envenomations by snakes and scorpions in North America, although uncommon, do occur, and the victims may seek medical treatment. Combined, snake and scorpion encounters result in more than 25,000 calls a year to poison centers. Although some similarities exist with respect to general signs of envenomation and treatment, specific nuances distinguish the medical care to be anticipated and therapies available. Regardless of geographic practice area, exposures will occur that may result in a significant envenomation. This article provides critical care nurses with fundamental knowledge of varied snake and scorpion envenomation presentations and treatments to assist in optimizing patient outcomes. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. The Hidden Snake in the Grass: Superior Detection of Snakes in Challenging Attentional Conditions.

    Directory of Open Access Journals (Sweden)

    Sandra C Soares

    Full Text Available Snakes have provided a serious threat to primates throughout evolution. Furthermore, bites by venomous snakes still cause significant morbidity and mortality in tropical regions of the world. According to the Snake Detection Theory (SDT Isbell, 2006; 2009, the vital need to detect camouflaged snakes provided strong evolutionary pressure to develop astute perceptual capacity in animals that were potential targets for snake attacks. We performed a series of behavioral tests that assessed snake detection under conditions that may have been critical for survival. We used spiders as the control stimulus because they are also a common object of phobias and rated negatively by the general population, thus commonly lumped together with snakes as "evolutionary fear-relevant". Across four experiments (N = 205 we demonstrate an advantage in snake detection, which was particularly obvious under visual conditions known to impede detection of a wide array of common stimuli, for example brief stimulus exposures, stimuli presentation in the visual periphery, and stimuli camouflaged in a cluttered environment. Our results demonstrate a striking independence of snake detection from ecological factors that impede the detection of other stimuli, which suggests that, consistent with the SDT, they reflect a specific biological adaptation. Nonetheless, the empirical tests we report are limited to only one aspect of this rich theory, which integrates findings across a wide array of scientific disciplines.

  15. The Hidden Snake in the Grass: Superior Detection of Snakes in Challenging Attentional Conditions.

    Science.gov (United States)

    Soares, Sandra C; Lindström, Björn; Esteves, Francisco; Ohman, Arne

    2014-01-01

    Snakes have provided a serious threat to primates throughout evolution. Furthermore, bites by venomous snakes still cause significant morbidity and mortality in tropical regions of the world. According to the Snake Detection Theory (SDT Isbell, 2006; 2009), the vital need to detect camouflaged snakes provided strong evolutionary pressure to develop astute perceptual capacity in animals that were potential targets for snake attacks. We performed a series of behavioral tests that assessed snake detection under conditions that may have been critical for survival. We used spiders as the control stimulus because they are also a common object of phobias and rated negatively by the general population, thus commonly lumped together with snakes as "evolutionary fear-relevant". Across four experiments (N = 205) we demonstrate an advantage in snake detection, which was particularly obvious under visual conditions known to impede detection of a wide array of common stimuli, for example brief stimulus exposures, stimuli presentation in the visual periphery, and stimuli camouflaged in a cluttered environment. Our results demonstrate a striking independence of snake detection from ecological factors that impede the detection of other stimuli, which suggests that, consistent with the SDT, they reflect a specific biological adaptation. Nonetheless, the empirical tests we report are limited to only one aspect of this rich theory, which integrates findings across a wide array of scientific disciplines.

  16. On some labelings of triangular snake and central graph of triangular snake graph

    Science.gov (United States)

    Agasthi, P.; Parvathi, N.

    2018-04-01

    A Triangular snake Tn is obtained from a path u 1 u 2 … u n by joining ui and u i+1 to a new vertex wi for 1≤i≤n‑1. A Central graph of Triangular snake C(T n ) is obtained by subdividing each edge of Tn exactly once and joining all the non adjacent vertices of Tn . In this paper the ways to construct square sum, square difference, Root Mean square, strongly Multiplicative, Even Mean and Odd Mean labeling for Triangular Snake and Central graph of Triangular Snake graphs are reported.

  17. First documented case of snake fungal disease in a free-ranging wild snake in Louisiana

    Science.gov (United States)

    Glorioso, Brad M.; Waddle, J. Hardin; Green, David E.; Lorch, Jeffrey M.

    2016-01-01

    Snake fungal disease (SFD) is a recently documented mycotic disease characterized by scabs or crusty scales, subcutaneous nodules, abnormal molting, cloudiness of the eyes (not associated with molting), and localized thickening or crusting of the skin. SFD has been documented in many species in the Eastern and Midwestern United States within the last decade. SFD has proven lethal in many snakes, and the disease is recognized as an emerging threat to wild snake populations. Here, we describe the first documented case of SFD in Louisiana in a free-ranging wild snake.

  18. Coil supporting device in nuclear fusion apparatus

    International Nuclear Information System (INIS)

    Hoshi, Ryo; Imura, Yasuya.

    1974-01-01

    Object: To secure intermediate fittings with a coil fixed thereon by an insulating tape to a fixed body by means of fittings, thereby supporting the coil in a narrow space. Structure: A coil is secured to intermediate fittings by means of an insulating tape, after which the intermediate fittings is mounted on a fixed body through fittings to support the coil in a narrow clearance portion between a plasma sealed vessel and a main coil. (Kamimura, M.)

  19. Simulations to study the static polarization limit for RHIC lattice

    Science.gov (United States)

    Duan, Zhe; Qin, Qing

    2016-01-01

    A study of spin dynamics based on simulations with the Polymorphic Tracking Code (PTC) is reported, exploring the dependence of the static polarization limit on various beam parameters and lattice settings for a practical RHIC lattice. It is shown that the behavior of the static polarization limit is dominantly affected by the vertical motion, while the effect of beam-beam interaction is small. In addition, the “nonresonant beam polarization” observed and studied in the lattice-independent model is also observed in this lattice-dependent model. Therefore, this simulation study gives insights of polarization evolution at fixed beam energies, that are not available in simple spin tracking. Supported by the U.S. Department of Energy (DE-AC02-98CH10886), Hundred-Talent Program (Chinese Academy of Sciences), and National Natural Science Foundation of China (11105164)

  20. Polarization Studies for the eRHIC Electron Storage Ring

    Energy Technology Data Exchange (ETDEWEB)

    Gianfelice-Wendt, Eliana [Fermilab; Tepikian, S. [Brookhaven

    2018-04-01

    A hadron/lepton collider with polarized beams has been under consideration by the scientific community since some years, in the U.S. and Europe. Among the various proposals, those by JLAB and BNL with polarized electron and proton beams are currently under closer study in the U.S. Experimenters call for the simultaneous storage of electron bunches with both spin helicity. In the BNL based Ring-Ring design, electrons are stored at top energy in a ring to be accommodated in the existing RHIC tunnel. The transversely polarized electron beam is injected into the storage ring at variable energies, between 5 and 18 GeV. Polarization is brought into the longitudinal direction at the IP by a couple of spin rotators. In this paper results of first studies of the attainable beam polarization level and lifetime in the storage ring at 18 GeV are presented.

  1. Silicon drift-chamber studies for possible use at RHIC

    International Nuclear Information System (INIS)

    Humanic, T.J.

    1990-01-01

    It is proposed to continue the program now underway at the University of Pittsburgh to study the feasibility of using silicon drift-chambers as particle tracking devices at RHIC. We are currently testing a UA6-type detector obtained from BNL, and propose to also study a new device that will become available this year: a cylindrical geometry detector design for NA45 (CERN). This new detector will be produced at BNL and the MPI-Institute in Munich and will incorporate updated techniques which should result in a reliable device with improved performance over the UA6-type detector. The one-year budget for this proposal is $50,079. 28 refs., 2 figs

  2. A p-Carbon CNI Polarimeter for RHIC

    International Nuclear Information System (INIS)

    Huang, H.; Bai, M.; Bunce, G.; Makdisi, Y.; Roser, T.; Imai, K.; Nakamura, M.; Tojo, J.; Yamamoto, K.; Zhu, L.; Bassalleck, B.; Eilerts, S.; Fields, D.E.; Lewis, B.; Smith, B.; Thomas, T. L.; Wolfe, D.; Goto, Y.; Hayoshi, N.; Ishihara, M.; Kurita, K.; Okamura, M.; Saito, N.; Taketani, A.; Doskow, J.; Kwiatkowski, K.; Lozowski, B.; Meyer, H.O.; Przewoski, B. V.; Rinckel, T.; Nurushev, S. B.; Strikhanov, M. N.; Runtzo, M. F.; Alekseev, I. G.; Svirida, D. N.; Deshpande, A.; Hughes, V.

    1999-01-01

    The RHIC spin program requires excellent polarimetry so that the knowledge of the beam polarization does not limit the errors on the experimental measurements. However, polarimetry of proton beams with energies higher than about 30 GeV poses a difficult challenge. For polarization monitoring during operation, a fast and reliable polarimeter is required that produces a polarization measurement with a 10% relative error within a few minutes. The p-Carbon elastic scattering in the Coulomb-Nuclear-Scattering (CNI) region has a calculable and large analyzing power, but detecting the recoil carbon needs sophisticated detector system and a very thin target. Experiment has been planned in the AGS. This paper describes the experimental setup in the AGS

  3. PHENIX EXPERIMENT AT RHIC: DECADAL PLAN 2004-2013

    International Nuclear Information System (INIS)

    ZAJC, W.

    2003-01-01

    The PHENIX Collaboration has developed a plan for the detailed investigation of quantum chromodynamics in the next decade. The demonstrated capabilities of the PHENIX experiment to measure rare processes in hadronic, leptonic and photonic channels, in combination with RHIC's unparalleled flexibility as a hadronic collider, provides a physics program of extraordinary breadth and depth. A superlative set of measurements to elucidate the states of both hot and cold nuclear matter, and to measure the spin structure of the proton has been identified. The components of this plan include: (1) Definitive measurements that will establish the nature of the matter created in nucleus+nucleus collisions, that will determine if the description of such matter as a quark-gluon plasma is appropriate, and that will quantify both the equilibrium and non-equilibrium features of the produced medium. (2) Precision measurements of the gluon structure of the proton, and of the spin structure of the gluon and sea-quark distributions of the proton via polarized proton+proton collisions. (3) Determination of the gluon distribution in cold nuclear matter using proton+nucleus collisions. Each of these fundamental fields of investigation will be addressed through a program of correlated measurements in some or all of the following channels: (1) Particle production at high transverse momentum, studied via single particle inclusive measurements of identified charged and neutral hadrons, multi-particle correlations and jet production. (2) Direct photon, photon+jet and virtual photon production. (3) Light and heavy vector mesons. (4) Heavy flavor production. These measurements, together with the established PHENIX abilities to identify hadrons at low transverse momentum, to perform detailed centrality selections, and to monitor polarization and luminosity with high precision create a superb opportunity for performing world-class science with PHENIX for the next decade. A portion of this program is

  4. Data acquisition for RHIC report of the working group

    International Nuclear Information System (INIS)

    Atiya, M.; Gibbard, B.; Hackenburg, R.

    1988-01-01

    As experimental configurations for RHIC become better defined, the requirements for data acquisition for each of the evolving experiments becomes susceptible to detailed analysis. An earlier contribution made it clear that the scale of these experiments makes demands on data acquisition that are at least as severe as some of the large-scale collider experiments being mounted at Fermilab and LEP. In this report, we attempt to answer the following questions: what sort of performance is required by each of the experiments; is there a single architecture flexible enough to accommodate all of the proposed experiments; what are the costs associated with such a implementation; and how far in advance of beam does a data acquisition implementation need to be started? 3 refs., 2 figs., 1 tab

  5. PHENIX EXPERIMENT AT RHIC: DECADAL PLAN 2004-2013

    Energy Technology Data Exchange (ETDEWEB)

    ZAJC,W.ET. AL.

    2003-11-30

    The PHENIX Collaboration has developed a plan for the detailed investigation of quantum chromodynamics in the next decade. The demonstrated capabilities of the PHENIX experiment to measure rare processes in hadronic, leptonic and photonic channels, in combination with RHIC's unparalleled flexibility as a hadronic collider, provides a physics program of extraordinary breadth and depth. A superlative set of measurements to elucidate the states of both hot and cold nuclear matter, and to measure the spin structure of the proton has been identified. The components of this plan include: (1) Definitive measurements that will establish the nature of the matter created in nucleus+nucleus collisions, that will determine if the description of such matter as a quark-gluon plasma is appropriate, and that will quantify both the equilibrium and non-equilibrium features of the produced medium. (2) Precision measurements of the gluon structure of the proton, and of the spin structure of the gluon and sea-quark distributions of the proton via polarized proton+proton collisions. (3) Determination of the gluon distribution in cold nuclear matter using proton+nucleus collisions. Each of these fundamental fields of investigation will be addressed through a program of correlated measurements in some or all of the following channels: (1) Particle production at high transverse momentum, studied via single particle inclusive measurements of identified charged and neutral hadrons, multi-particle correlations and jet production. (2) Direct photon, photon+jet and virtual photon production. (3) Light and heavy vector mesons. (4) Heavy flavor production. These measurements, together with the established PHENIX abilities to identify hadrons at low transverse momentum, to perform detailed centrality selections, and to monitor polarization and luminosity with high precision create a superb opportunity for performing world-class science with PHENIX for the next decade. A portion of this

  6. LINEAR AND NONLINEAR CORRECTIONS IN THE RHIC INTERACTION REGIONS

    International Nuclear Information System (INIS)

    PILAT, F.; CAMERON, P.; PTITSYN, V.; KOUTCHOUK, J.P.

    2002-01-01

    A method has been developed to measure operationally the linear and non-linear effects of the interaction region triplets, that gives access to the multipole content through the action kick, by applying closed orbit bumps and analyzing tune and orbit shifts. This technique has been extensively tested and used during the RHIC operations in 2001. Measurements were taken at 3 different interaction regions and for different focusing at the interaction point. Non-linear effects up to the dodecapole have been measured as well as the effects of linear, sextupolar and octupolar corrections. An analysis package for the data processing has been developed that through a precise fit of the experimental tune shift data (measured by a phase lock loop technique to better than 10 -5 resolution) determines the multipole content of an IR triplet

  7. Real-World Sorting of RHIC Superconducting Magnets

    International Nuclear Information System (INIS)

    Wei, J.; Gupta, R.; Harrison, M.; Jain, A.; Peggs, S.; Thompson, P.; Trbojevic, D.; Wanderer, P.

    1999-01-01

    During the seven-year construction of the Relativistic Heavy Ion Collider (RHIC), more than 1700 superconducting dipoles, quadrupoles, sextupoles, and multi-layer correctors have been constructed and installed. These magnets have been sorted at several production stages to optimize their performance and reliability. For arc magnets, priorities have bene put first on quench performance and operational risk minimization, second on field transfer function and other first-order quantities, and finally on nonlinear field errors which were painstakingly optimized at design. For Interaction-Region (IR) magnets, sorting is applied to select the best possible combination of magnets for the low-β interaction points (IP). This paper summarizes the history of this real-world sorting process

  8. Stochastic cooling and intra-beam scattering in RHIC

    International Nuclear Information System (INIS)

    Wei, J.

    1993-01-01

    During the storage of the heavy ion beam in the Relativistic Heavy Ion Collider (RHIC), the luminosity deterioration due to beam growth and particle loss caused by intra-beam scattering (IBS) is of primary concern. In this paper, the authors study compensation methods using bunched beam stochastic cooling. With longitudinal and transverse stochastic cooling of 4--8 GHz bandwidth, the longitudinal beam loss resulting from the inadequacy of the rf voltage can be eliminated, and the transverse normalized beam emittance can be confined to about 30π mm·mrad. With such an emittance, the β* at the crossing point can be lowered under 1 meter without exceeding the transverse aperture limit at the focusing triplets. The achievable luminosity can thus be significantly improved

  9. Physics with the collider detectors at RHIC and the LHC

    International Nuclear Information System (INIS)

    Thomas, J.; Hallman, T.

    1995-01-01

    On January 8, 1995, over 180 participants gathered to hear the QM95 preconference workshop on 'Physics with the Collider Detectors at RHIC and the LHC'. The goal was to bring together the experimentalists from a wide community of hadron and heavy ion collider detector collaborations. The speakers were encouraged to present the current status of their detectors, with all the blemishes, and the audience was encouraged to share their successes and failures in approaching similar detector design issues. The presentations were excellent and the discussions were lively and stimulating. The editors hope that the reader will find these proceedings to be equally stimulating. Separate abstracts have been submitted to the energy database from articles in this report

  10. SEARCH FOR A RELIABLE STORAGE ARCHITECTURE FOR RHIC

    International Nuclear Information System (INIS)

    BINELLO, S.; KATZ, R.A.; MORRIS, J.T.

    2007-01-01

    Software used to operate the Relativistic Heavy Ion Collider (RHIC) resides on one operational RAID storage system. This storage system is also used to store data that reflects the status and recent history of accelerator operations. Failure of this system interrupts the operation of the accelerator as backup systems are brought online. In order to increase the reliability of this critical control system component, the storage system architecture has been upgraded to use Storage Area Network (SAN) technology and to introduce redundant components and redundant storage paths. This paper describes the evolution of the storage system, the contributions to reliability that each additional feature has provided, further improvements that are being considered, and real-life experience with the current system

  11. SEARCH FOR A RELIABLE STORAGE ARCHITECTURE FOR RHIC.

    Energy Technology Data Exchange (ETDEWEB)

    BINELLO,S.; KATZ, R.A.; MORRIS, J.T.

    2007-10-15

    Software used to operate the Relativistic Heavy Ion Collider (RHIC) resides on one operational RAID storage system. This storage system is also used to store data that reflects the status and recent history of accelerator operations. Failure of this system interrupts the operation of the accelerator as backup systems are brought online. In order to increase the reliability of this critical control system component, the storage system architecture has been upgraded to use Storage Area Network (SAN) technology and to introduce redundant components and redundant storage paths. This paper describes the evolution of the storage system, the contributions to reliability that each additional feature has provided, further improvements that are being considered, and real-life experience with the current system.

  12. Physics with the collider detectors at RHIC and the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, J.; Hallman, T. [eds.

    1995-07-15

    On January 8, 1995, over 180 participants gathered to hear the QM95 preconference workshop on `Physics with the Collider Detectors at RHIC and the LHC`. The goal was to bring together the experimentalists from a wide community of hadron and heavy ion collider detector collaborations. The speakers were encouraged to present the current status of their detectors, with all the blemishes, and the audience was encouraged to share their successes and failures in approaching similar detector design issues. The presentations were excellent and the discussions were lively and stimulating. The editors hope that the reader will find these proceedings to be equally stimulating. Separate abstracts have been submitted to the energy database from articles in this report.

  13. Pion-nucleus interactions and the STAR experiment at RHIC

    International Nuclear Information System (INIS)

    Moore, C.F.

    1993-09-01

    This report summarizes the work carried out by personnel from the University of Texas at Austin at the Los Alamos Clinton P. Anderson Meson Physics Facility (LAMPF) during the calendar years 1990--1993 and on the STAR experiment at RHIC under grant DE-FGO5-87ER40343 between the University of Texas at Austin and the United States Department of Energy. A brief overview of work supported by this grant is given in Section 2. An account of the study of the double giant resonances in pion double charge exchange forms Section 3. This report contains a list of published papers and preprints in Section 6, invited talks in Section 7, and abstracts in Section 8. These papers summarize experiments involving participants supported by this grant and indicate the work accomplished by these participants in this program of medium energy nuclear physics research. Section 9 contains a list of personnel who have participated in this research program

  14. A 4π tracking magnetic spectrometer for RHIC

    International Nuclear Information System (INIS)

    Lindenbaum, S.J.

    1988-01-01

    A tracking magnetic spectrometer based on large Time Projection Chambers (TPC) was previously proposed to measure the momentum of charged particles emerging from the RHIC beam pipe at angles larger than four degrees and to identify the particle type for those beyond fifteen degrees with momenta up to 700 MeV/c, which is a large fraction of the final charged particles emitted by a low cm rapidity quark-gluon plasma. Experimental progress in the successful performance of a TPC developed for AGS E-810 is reported. We have also included typical results of our event generator which contains an interface of an improved HIJET and a plasma bubble model. Typical plasma signals one can expect from this model are presented. 4 refs., 9 figs

  15. Noise estimation of beam position monitors at RHIC

    International Nuclear Information System (INIS)

    Shen, X.; Bai, M.

    2014-01-01

    Beam position monitors (BPM) are used to record the average orbits and transverse turn-by-turn displacements of the beam centroid motion. The Relativistic Hadron Ion Collider (RHIC) has 160 BPMs for each plane in each of the Blue and Yellow rings: 72 dual-plane BPMs in the insertion regions (IR) and 176 single-plane modules in the arcs. Each BPM is able to acquire 1024 or 4096 consecutive turn-by-turn beam positions. Inevitably, there are broadband noisy signals in the turn-by-turn data due to BPM electronics as well as other sources. A detailed study of the BPM noise performance is critical for reliable optics measurement and beam dynamics analysis based on turn-by-turn data.

  16. B factory at RHIC [Relativistic Heavy Ion Collider]?

    International Nuclear Information System (INIS)

    Lockyer, N.S.; Van Berg, R.; Newcomer, F.M.

    1988-01-01

    A dedicated B physics experiment located in the proposed Relativistic Heavy Ion Collider at Brookhaven (RHIC) is considered. The machine may operate in a p-p mode with a luminosity in excess of 10 32 cm/sup /minus/2/ sec/sup /minus/1/ at 250 /times/ 250 GeV. The estimated B/bar B/ cross section at these energies is about 10 μbarns and a run of 10 7 sec would produce roughly 10 10 B/bar B/ pairs. A comparison to similar ideas proposed for the Fermilab Tevatron Upgrade and the SSC are discussed. The most ambitious physics objective of such an experiment would be the study of CP nonconservation. Particular emphasis at this workshop was given to the self tagging mode B → K + π/sup /minus//. Experimental techniques developed during this experiment would be extremely useful for more ambitious projects anticipated at the SSC. 36 refs., 10 figs

  17. THE ERL HIGH-ENERGY COOLER FOR RHIC

    International Nuclear Information System (INIS)

    BEN-ZVI, I.

    2006-01-01

    Electron cooling [1] entered a new era with the July 2005 cooling of the Tevatron recycler ring [2] at Fermilab, using γ = 9.5. Considering that the cooling rate decreases as faster than γ 2 and the electron energy forces higher electron currents, new acceleration techniques, high-energy electron cooling presents special challenges to the accelerator scientists and engineers. For example, electron cooling of RHIC at collisions requires electron beam energy up to about 54 MeV at an average current of between 50 to 100 mA and a particularly bright electron beam. The accelerator chosen to generate this electron beam is a superconducting Energy Recovery Linac (ERL) with a superconducting RF gun with a laser-photocathode

  18. The electromagnetic calorimeter for the solenoidal tracker at RHIC. A Conceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Beddo, M.E.; Bielick, E.; Dawson, J.W. [Argonne National Lab., IL (United States)] [and others; The STAR EMC Collaboration

    1993-09-22

    This report discusses the following on the electromagnetic calorimeter for the solenoidal tracker at RHIC: conceptual design; the physics of electromagnetic calorimetry in STAR; trigger capability; integration into STAR; and cost, schedule, manpower, and funding.

  19. and two-particle spectra at RHIC based on a hydrodynamical model

    Indian Academy of Sciences (India)

    parametrize the initial energy density distribution and net baryon number distribution as in figure 1. For both RHIC and ... Figure 2 shows pseudorapidity distribution of charged hadrons and transverse momen- ... Network Center. References.

  20. RHIC: What We Have Learned So Far (434th Brookhaven Lecture)

    International Nuclear Information System (INIS)

    O'Brien, Edward

    2008-01-01

    One of the world's premiere nuclear research facilities, the Relativistic Heavy Ion Collider (RHIC) at Brookhaven Lab is just completing its eighth year of physics operation. During the past eight years, RHIC's primary physics program has emphasized the creation, observation and explanation of nuclear matter created at temperatures and densities that last existed in the universe some 13.7 billion years ago. RHIC was built to study the strong force, which holds quarks and gluons together within the nucleus of an atom, with the goal of observing a plasma of quarks and gluons freed from the atomic nucleus. The new state of matter that was created, however, was quite different. Dr. O'Brien will discuss what RHIC scientists expected versus what they discovered, and how this finding both challenges existing theory and provides an opportunity to understand the strong force better.

  1. Helium release rates and ODH calculations from RHIC magnet cooling line failure

    Energy Technology Data Exchange (ETDEWEB)

    Liaw, C.J.; Than, Y.; Tuozzolo, J.

    2011-03-28

    A catastrophic failure of the magnet cooling lines, similar to the LHC superconducting bus failure incident, could discharge cold helium into the RHIC tunnel and cause an Oxygen Deficiency Hazard (ODH) problem. A SINDA/FLUINT{reg_sign} model, which simulated the 4.5K/4 atm helium flowing through the magnet cooling system distribution lines, then through a line break into the insulating vacuum volumes and discharging via the reliefs into the RHIC tunnel, had been developed. Arc flash energy deposition and heat load from the ambient temperature cryostat surfaces are included in the simulations. Three typical areas: the sextant arc, the Triplet/DX/D0 magnets, and the injection area, had been analyzed. Results, including helium discharge rates, helium inventory loss, and the resulting oxygen concentration in the RHIC tunnel area, are reported. Good agreement had been achieved when comparing the simulation results, a RHIC sector depressurization test measurement, and some simple analytical calculations.

  2. ERL-BASED LEPTON-HADRON COLLIDERS: eRHIC AND LHeC

    CERN Document Server

    Zimmermann, F

    2013-01-01

    Two hadron-ERL colliders are being proposed. The Large Hadron electron Collider (LHeC) plans to collide the high-energy protons and heavy ions in the Large Hadron Collider (LHC) at CERN with 60-GeV polarized electrons or positrons. The baseline scheme for this facility adds to the LHC a separate recirculating superconducting (SC) lepton linac with energy recovery, delivering a lepton current of 6.4mA. The electron-hadron collider project eRHIC aims to collide polarized (and unpolarized) electrons with a current of 50 (220) mA and energies in the range 5–30 GeV with a variety of hadron beams— heavy ions as well as polarized light ions— stored in the existing Relativistic Heavy Ion Collider (RHIC) at BNL. The eRHIC electron beam will be generated in an energy recovery linac (ERL) installed inside the RHIC tunnel.

  3. Safe Handling of Snakes in an ED Setting.

    Science.gov (United States)

    Cockrell, Melanie; Swanson, Kristofer; Sanders, April; Prater, Samuel; von Wenckstern, Toni; Mick, JoAnn

    2017-01-01

    Efforts to improve consistency in management of snakes and venomous snake bites in the emergency department (ED) can improve patient and staff safety and outcomes, as well as improve surveillance data accuracy. The emergency department at a large academic medical center identified an opportunity to implement a standardized process for snake disposal and identification to reduce staff risk exposure to snake venom from snakes patients brought with them to the ED. A local snake consultation vendor and zoo Herpetologist assisted with development of a process for snake identification and disposal. All snakes have been identified and securely disposed of using the newly implemented process and no safety incidents have been reported. Other emergency department settings may consider developing a standardized process for snake disposal using listed specialized consultants combined with local resources and suppliers to promote employee and patient safety. Copyright © 2017 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.

  4. GLOBAL AND LOCAL COUPLING COMPENSATION EXPERIMENTS IN RHIC USING AC DIPOLES

    International Nuclear Information System (INIS)

    CALAGA, R.; FRANCHI, A., TOMAS, R.; CERN)

    2006-01-01

    Compensation of transverse coupling during the RHIC energy ramp has been proven to be non-trivial and tedious. The lack of accurate knowledge of the coupling sources has initiated several efforts to develop fast techniques using turn-by-turn BPM data to identify and compensate these sources. This paper aims to summarize the beam experiments performed to measure the coupling, matrix and resonance driving terms with the aid of RHIC ac dipoles at injection energy

  5. Resummed pQCD for $W^{+-}$ and $Z^{0}$ transverse momentum spectra at RHIC and LHC

    CERN Document Server

    Xiao Fei Zhang

    2003-01-01

    The transverse momentum distributions of W/sup +or-/ and Z/sup 0/ are predicted at RHIC and LHC. A resummation formalism with power corrections to the renormalization group equations is used. Shadowing effects are discussed and found to be unimportant at RHIC, but important for LHC. We study the enhancement of power corrections due to multiple scattering in nuclear collisions and numerically illustrate the weak effects of the dependence on the nuclear mass. (12 refs).

  6. Design of the commissioning software for the AGS to RHIC transfer line

    International Nuclear Information System (INIS)

    Trahern, C.G.; Saltmarsh, C.; Satogata, T.; Kewisch, J.; Sathe, S.; D'ottavio, T.; Tepikian, S.; Shea, D.

    1995-01-01

    RHIC accelerator physicists and engineers have collaboratively specified the control system software for the commissioning of the AGS to RHIC transfer line (ATR) to occur in the fall of 1995. This paper summarizes the design and progress to date. The authors discuss the basic physics/engineering device model that they use to understand process and data flows, and describe the architecture and tools they will use to build the application level software

  7. Technology transfer for industrial production of superconducting magnets for the RHIC project at BNL

    International Nuclear Information System (INIS)

    Wanderer, P.; Anerella, M.D.; Greene, A.F.; Kelly, E.; Willen, E.

    1994-01-01

    Industrial production of superconducting magnets for the Relativistic Heavy Ion Collider (RHIC) has begun. The R ampersand D for the magnets was carried out at BNL. Following the award of built-to-print contracts, staff from the laboratory and the vendors worked toward transferring both design principles and practical details to an industrial framework for cost effective production. All magnets made thus far have been acceptable for use in RHIC

  8. New progress in snake mitochondrial gene rearrangement.

    Science.gov (United States)

    Chen, Nian; Zhao, Shujin

    2009-08-01

    To further understand the evolution of snake mitochondrial genomes, the complete mitochondrial DNA (mtDNA) sequences were determined for representative species from two snake families: the Many-banded krait, the Banded krait, the Chinese cobra, the King cobra, the Hundred-pace viper, the Short-tailed mamushi, and the Chain viper. Thirteen protein-coding genes, 22-23 tRNA genes, 2 rRNA genes, and 2 control regions were identified in these mtDNAs. Duplication of the control region and translocation of the tRNAPro gene were two notable features of the snake mtDNAs. These results from the gene rearrangement comparisons confirm the correctness of traditional classification schemes and validate the utility of comparing complete mtDNA sequences for snake phylogeny reconstruction.

  9. 2015 OLC FEMA Lidar: Snake River, ID

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Quantum Spatial has collected Light Detection and Ranging (LiDAR) data for the Oregon LiDAR Consortium (OLC) Snake River FEMA study area. This study area is located...

  10. First Observation of a Snake Depolarizing Resonance

    International Nuclear Information System (INIS)

    Phelps, R.; Anferov, V.; Blinov, B.; Crandell, D.; Koutin, S.; Krisch, A.; Liu, T.; Ratner, L.; Wong, V.; Chu, C.; Lee, S.; Rinckel, T.; Schwandt, P.; Sperisen, F.; Stephenson, E.; von Przewoski, B.; Sato, H.

    1997-01-01

    Using a 104MeV stored polarized proton beam and a full Siberian snake, we recently found evidence for a so-called open-quotes snakeclose quotes depolarizing resonance. A full Siberian snake forces the spin tune ν s to be a half integer. Thus, if the vertical betatron tune ν y is set near a quarter integer, then the ν s =n±2ν y second-order snake resonance can depolarize the beam. Indeed, with a full Siberian snake, we found a deep depolarization dip when ν y was equal to 4.756; moreover, when ν y was changed to 4.781, the deep dip disappeared and the polarization was preserved. copyright 1997 The American Physical Society

  11. Friction enhancement in concertina locomotion of snakes

    Science.gov (United States)

    Marvi, Hamidreza; Hu, David L.

    2012-01-01

    Narrow crevices are challenging terrain for most organisms and biomimetic robots. Snakes move through crevices using sequential folding and unfolding of their bodies in the manner of an accordion or concertina. In this combined experimental and theoretical investigation, we elucidate this effective means of moving through channels. We measure the frictional properties of corn snakes, their body kinematics and the transverse forces they apply to channels of varying width and inclination. To climb channels inclined at 60°, we find snakes use a combination of ingenious friction-enhancing techniques, including digging their ventral scales to double their frictional coefficient and pushing channel walls transversely with up to nine times body weight. Theoretical modelling of a one-dimensional n-linked crawler is used to calculate the transverse force factor of safety: we find snakes push up to four times more than required to prevent sliding backwards, presumably trading metabolic energy for an assurance of wall stability. PMID:22728386

  12. A test of reproductive power in snakes.

    Science.gov (United States)

    Boback, Scott M; Guyer, Craig

    2008-05-01

    Reproductive power is a contentious concept among ecologists, and the model has been criticized on theoretical and empirical grounds. Despite these criticisms, the model has successfully predicted the modal (optimal) size in three large taxonomic groups and the shape of the body size distribution in two of these groups. We tested the reproductive power model on snakes, a group that differs markedly in physiology, foraging ecology, and body shape from the endothermic groups upon which the model was derived. Using detailed field data from the published literature, snake-specific constants associated with reproductive power were determined using allometric relationships of energy invested annually in egg production and population productivity. The resultant model accurately predicted the mode and left side of the size distribution for snakes but failed to predict the right side of that distribution. If the model correctly describes what is possible in snakes, observed size diversity is limited, especially in the largest size classes.

  13. Experimental Infection of Snakes with Ophidiomyces ophiodiicola Causes Pathological Changes That Typify Snake Fungal Disease.

    Science.gov (United States)

    Lorch, Jeffrey M; Lankton, Julia; Werner, Katrien; Falendysz, Elizabeth A; McCurley, Kevin; Blehert, David S

    2015-11-17

    Snake fungal disease (SFD) is an emerging skin infection of wild snakes in eastern North America. The fungus Ophidiomyces ophiodiicola is frequently associated with the skin lesions that are characteristic of SFD, but a causal relationship between the fungus and the disease has not been established. We experimentally infected captive-bred corn snakes (Pantherophis guttatus) in the laboratory with pure cultures of O. ophiodiicola. All snakes in the infected group (n = 8) developed gross and microscopic lesions identical to those observed in wild snakes with SFD; snakes in the control group (n = 7) did not develop skin infections. Furthermore, the same strain of O. ophiodiicola used to inoculate snakes was recovered from lesions of all animals in the infected group, but no fungi were isolated from individuals in the control group. Monitoring progression of lesions throughout the experiment captured a range of presentations of SFD that have been described in wild snakes. The host response to the infection included marked recruitment of granulocytes to sites of fungal invasion, increased frequency of molting, and abnormal behaviors, such as anorexia and resting in conspicuous areas of enclosures. While these responses may help snakes to fight infection, they could also impact host fitness and may contribute to mortality in wild snakes with chronic O. ophiodiicola infection. This work provides a basis for understanding the pathogenicity of O. ophiodiicola and the ecology of SFD by using a model system that incorporates a host species that is easy to procure and maintain in the laboratory. Skin infections in snakes, referred to as snake fungal disease (SFD), have been reported with increasing frequency in wild snakes in the eastern United States. While most of these infections are associated with the fungus Ophidiomyces ophiodiicola, there has been no conclusive evidence to implicate this fungus as a primary pathogen. Furthermore, it is not understood why the

  14. Prey handling and diet of Louisiana pine snakes (Pituophis ruthveni) and black pine snakes (P. melanoleucus lodingi), with comparisons to other selected colubrid snakes

    Science.gov (United States)

    D. Craig Rudolph; Shirley J. Burgdorf; Richard N. Conner; Christopher S. Collins; Daniel Saenz; Richard R. Schaefer; Toni Trees; C. Michael Duran; Marc Ealy; John G. Himes

    2002-01-01

    Diet and prey handling behavior were determined for Louisiana pine snakes (Pituophis ruthveni) and black pine snakes (P. melanoleucus lodingi). Louisiana pine snakes prey heavily on Baird's pocket gophers (Geomys breviceps), with which they are sympatric, and exhibit specialized behaviors that facilitate...

  15. Evaluation of Snake Bites with Bedside Ultrasonography

    Directory of Open Access Journals (Sweden)

    Josef E Jolissaint

    2018-04-01

    Full Text Available History of present illness: While watering his lawn, a 36-year-old man felt two sharp bites to his bilateral ankles. He reports that he then saw a light brown, 2-foot snake slither away from him. He came to the emergency department because of pain and swelling in his ankles and inability to bear weight. Physical examination revealed bilateral ankle swelling and puncture marks on his left lateral heel and medial right ankle. Palpation, passive flexion and extension elicited severe pain bilaterally. Blood work including prothrombin time (PT, partial thromboplastin time (PTT, international normalized ratio (INR, and fibrinogen were within normal limits. Consultation with Poison Control indicated the snake was likely a copperhead, which is a venomous snake whose bites rarely require antivenin. Significant findings: In this case, ultrasonography of the lateral surface of the left foot revealed soft tissue edema (red arrow and fluid collection (white asterisk adjacent to the extensor tendon (white arrow. The edematous area resembles cobblestones, with hypoechoic areas of fluid spanning relatively hyperechoic fat lobules. The tendon is surrounded by anechoic fluid, expanding the potential space in the sheath. No hyperechoic foreign objects were noted. Discussion: The patient was diagnosed with soft tissue injury and extensor tenosynovitis after a snake envenomation. Snake venom contains metalloproteinases and other enzymatic proteins that cause local tissue edema and necrosis.1 After a snake bite, ultrasound can be used to assess for retained fangs, soft tissue edema, tendon sheath fluid, muscle fasciculation, and injury to deeper musculature that may not be readily apparent on physical exam.2,3 Most patients with tenosynovitis will recover with immobilization of the joint and non-steroidal anti-inflammatory medications.4 Rarely, the tendon may become infected requiring antibiotics and surgical intervention.4 Topics: Ultrasound, snake envenomation

  16. A partial snake for the AGS

    International Nuclear Information System (INIS)

    Ratner, L.G.

    1990-01-01

    Based on snake experiments at the Indian University Cyclotron Facility and computer simulations at Brookhaven National Laboratory, as well as the conclusions of a BNL mini-workshop, we feel that a partial Siberian snake is a practical device for the AGS. It is anticipated that such a device could reduce the polarized beam tune-up time from 2--3 weeks to 2--3 days

  17. Cardiovascular responses of snakes to hypergravity

    Science.gov (United States)

    Lillywhite, H. B.; Ballard, R. E.; Hargens, A. R.; Rosenberg, H. I.

    1997-01-01

    Snakes have provided useful vertebrate models for understanding circulatory adaptation to gravity, attributable to their elongate body shape and evolutionary diversificaton in terms of ecology and behavior. Recently we have studied cardiovascular responses of snakes to hypergravic acceleration forces produced acutely in the head-to-tail direction (+Gz) on a short-arm centrifuge. Snakes were held in a nearly straight position within a horizontal plastic tube and subjected to a linear force gradient during acceleration. Carotid blood flow provided an integrated measure of cardiovascular performance. Thus, cardiovascular tolerance of snakes to stepwise increments of Gz was measured as the caudal Gz force at which carotid blood flow ceased. Tolerance to increasing Gz varies according to adaptive evolutionary history inferred from the ecology and behavior of species. With respect to data for six species we investigated, multiple regression analysis demonstrates that Gz tolerance correlates with gravitational habitat, independently of body length. Relative to aquatic and non-climbing species, carotid blood flow is better maintained in arboreal or scansorial species, which tolerate hypergravic forces of +2 to +3.5 Gz. Additionally, semi-arboreal rat snakes (Elaphe obsoleta) exhibit plasticity of responses to long-term, intermittent +1.5 Gz stress. Compared to non-acclimated controls, acclimated snakes show greater increases of heart rate during head-up tilt or acceleration, greater sensitivity of arterial pressure to circulating catecholamines, higher blood levels of prostaglandin ratios favorable to maintenance of arterial blood pressure, and medial hypertrophy in major arteries and veins. As in other vertebrates, Gz tolerance of snakes is enhanced by acclimation, high arterial pressure, comparatively large blood volume, and body movements. Vascular studies of snakes suggest the importance to acclimation of local responses involving vascular tissue, in addition to

  18. Are snake populations in widespread decline?

    OpenAIRE

    Reading, C. J.; Luiselli, L. M.; Akani, G. C.; Bonnet, X.; Amori, G.; Ballouard, J. M.; Filippi, E.; Naulleau, G.; Pearson, D.; Rugiero, L.

    2010-01-01

    Long-term studies have revealed population declines in fishes, amphibians, reptiles, birds and mammals. In birds, and particularly amphibians, these declines are a global phenomenon whose causes are often unclear. Among reptiles, snakes are top predators and therefore a decline in their numbers may have serious consequences for the functioning of many ecosystems. Our results show that, of 17 snake populations (eight species) from the UK, France, Italy, Nigeria and Australia, 11 have declined ...

  19. Negative snakes in JET: evidence for negative shear

    Energy Technology Data Exchange (ETDEWEB)

    Gill, R D; Alper, B; Edwards, A W [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Pearson, D [Reading Univ. (United Kingdom)

    1994-07-01

    The signature of the negative snakes from the soft X-ray cameras is very similar to the more usual snakes except that the localised region of the snake has, compared with its surroundings, decreased rather than increased emission. Circumstances where negative snakes have been seen are reviewed. The negative snake appears as a region of increased resistance and of increased impurity density. The relationship between the shear and the current perturbation is shown, and it seem probable that the magnetic shear is reversed at the point of the negative snake, i.e. that q is decreasing with radius. 6 refs., 6 figs.

  20. Negative snakes in JET: evidence for negative shear

    International Nuclear Information System (INIS)

    Gill, R.D.; Alper, B.; Edwards, A.W.

    1994-01-01

    The signature of the negative snakes from the soft X-ray cameras is very similar to the more usual snakes except that the localised region of the snake has, compared with its surroundings, decreased rather than increased emission. Circumstances where negative snakes have been seen are reviewed. The negative snake appears as a region of increased resistance and of increased impurity density. The relationship between the shear and the current perturbation is shown, and it seem probable that the magnetic shear is reversed at the point of the negative snake, i.e. that q is decreasing with radius. 6 refs., 6 figs