|
|
| Line 1: |
Line 1: |
| {{Hadron colliders
| | Alyson is the title people use to contact me and I believe it sounds fairly good when you say it. For years he's been living in Alaska and he doesn't strategy on changing it. What me and my family members love is bungee leaping but I've been taking on new issues lately. Office supervising is my occupation.<br><br>Here is my web site are psychics real [[http://medisys-africa.com/content/basic-steps-may-help-you-your-way-brand-new-hobby link web site medisys-africa.com]] |
| |Image=
| |
| |Caption=The Relativistic Heavy Ion Collider at [[Brookhaven National Laboratory]]. Note especially the second, independent ring behind the blue striped one. Barely visible and between the white and red pipes on the left wall, is the orange [[Crash Cord]], which should be used to stop the beam in case a person is still left in the tunnel.
| |
| }}
| |
| | |
| The '''Relativistic Heavy Ion Collider''' ('''RHIC''', {{IPAc-en|ˈ|r|ɪ|k}}) is one of only two operating heavy-[[ion]] [[collider]]s, and the only [[spin (physics)|spin]]-polarized [[proton]] [[collider]] ever built. Located at [[Brookhaven National Laboratory]] (BNL) in [[Upton, New York]], and used by an international team of researchers, it is the only operating particle collider in the US.<ref>
| |
| {{cite journal
| |
| |author=M. Harrison, T. Ludlam, S. Ozaki
| |
| |year=2003
| |
| |title=RHIC Project Overview
| |
| |journal=[[Nuclear Instruments and Methods in Physics Research A]]
| |
| |volume=499 |issue=2–3 |page=235
| |
| |doi=10.1016/S0168-9002(02)01937-X
| |
| |bibcode = 2003NIMPA.499..235H }}</ref><ref>
| |
| {{cite journal
| |
| |author=M. Harrison, S. Peggs, T. Roser
| |
| |year=2002
| |
| |title=The RHIC Accelerator
| |
| |journal=[[Annual Review of Nuclear and Particle Science]]
| |
| |volume=52 |page=425
| |
| |doi=10.1146/annurev.nucl.52.050102.090650
| |
| |bibcode = 2002ARNPS..52..425H }}</ref><ref>
| |
| {{cite journal
| |
| |author=E.D. Courant
| |
| |year=2003
| |
| |title=Accelerators, Colliders, and Snakes
| |
| |journal=[[Annual Review of Nuclear and Particle Science]]
| |
| |volume=53 |page=1
| |
| |doi=10.1146/annurev.nucl.53.041002.110450
| |
| |bibcode = 2003ARNPS..53....1C }}</ref> By using RHIC to collide [[ion]]s traveling at [[special relativity|relativistic]] speeds, physicists study the [[quark–gluon plasma|primordial form]] of matter that existed in the [[universe]] shortly after the [[Big Bang]].<ref>
| |
| {{cite journal
| |
| |author=M. Riordan, W.A. Zajc
| |
| |year=2006
| |
| |title=The First Few Microseconds
| |
| |url=http://www.sciam.com/article.cfm?articleID=0009A312-037F-1448-837F83414B7F014D
| |
| |journal=[[Scientific American]]
| |
| |volume=294 |issue=5 |page=34
| |
| |doi=10.1038/scientificamerican0506-34A
| |
| }}</ref><ref>
| |
| {{cite web
| |
| |author=S. Mirsky, W.A Zajc, J. Chaplin
| |
| |date=26 April 2006
| |
| |title=Early Universe, Benjamin Franklin Science, Evolution Education
| |
| |url=http://www.scientificamerican.com/podcast/episode.cfm?id=000F3F76-D5E6-144E-95E683414B7F0000
| |
| |work=Science Talk
| |
| |publisher=Scientific American
| |
| |accessdate=2010-02-16
| |
| }} ([http://podcast.sciam.com/sa_podcast_060426.mp3 Listen])</ref> By colliding spin-polarized protons, the spin structure of the [[proton]] is explored.
| |
| | |
| RHIC is now the second-highest-energy heavy-ion collider in the world. As of November 7, 2010, the [[LHC]] has collided heavy ions of lead at higher energies than RHIC.<ref>
| |
| {{cite web
| |
| |date=8 November 2010
| |
| |title=CERN Completes Transition to Lead-Ion Running at the LHC
| |
| |url=http://press.web.cern.ch/press/PressReleases/Releases2010/PR21.10E.html
| |
| |publisher=[[CERN]]
| |
| |accessdate=2010-11-08
| |
| }}</ref>
| |
| The LHC operating time for ions is limited to about one month per year.
| |
| | |
| In 2010, RHIC physicists published results of temperature measurements from earlier experiments which concluded that temperatures in excess of 345 MeV (4 trillion kelvin or 7 trillion degrees Fahrenheit) had been achieved in gold ion collisions, and that these collision temperatures resulted in the breakdown of "normal matter" and the creation of a liquid-like [[quark-gluon plasma]].<ref>
| |
| {{cite web
| |
| |author=A. Trafton
| |
| |date=9 February 2010
| |
| |title=Explained: Quark gluon plasma
| |
| |url=http://web.mit.edu/newsoffice/2010/exp-quark-gluon-0609.html
| |
| |publisher=[[MITnews]]
| |
| }}</ref>
| |
| | |
| ==The accelerator==
| |
| RHIC is an intersecting [[storage ring]] [[particle accelerator]]. Two independent rings (arbitrarily denoted as "Blue" and "Yellow" rings) circulate heavy [[ion]]s and/or [[proton]]s in opposite directions and allow a virtually free choice of colliding positively [[charged particle]]s (the [[#The future|eRHIC]] upgrade will allow collisions between positively and negatively charged particles). The RHIC double storage ring is itself [[hexagon]]ally shaped and {{val|3834|u=m}} long in circumference, with curved edges in which stored particles are deflected and focused by 1,740 [[Superconductor|superconducting]] [[magnet]]s using [[niobium-titanium]] conductors. The [[dipole magnet]]s operate at {{val|3.45|u=[[Tesla (unit)|T]]}}.<ref>
| |
| {{cite web
| |
| |author=P. Wanderer
| |
| |date=22 February 2008
| |
| |title=RHIC
| |
| |url=http://www.bnl.gov/magnets/RHIC/RHIC.asp
| |
| |publisher=[[Brookhaven National Laboratory]], Superconducting Magnet Division
| |
| |accessdate=2010-02-16
| |
| }}</ref> The six interaction points (between the particles circulating in the two rings) are at the middle of the six relatively straight sections, where the two rings cross, allowing the particles to collide. The interaction points are enumerated by clock positions, with the injection near 6 o'clock. Two large experiments, STAR and PHENIX, are located at 6 and 8 o'clock respectively.<ref>See
| |
| {{cite web
| |
| |author=
| |
| |date=
| |
| |title=RHIC Accelerators
| |
| |url=http://www.bnl.gov/RHIC/complex.asp
| |
| |publisher=[[Brookhaven National Laboratory]]
| |
| |accessdate=2010-02-16
| |
| }}</ref>
| |
| | |
| A particle passes through several stages of [[wikt:booster|booster]]s before it reaches the RHIC storage ring. The first stage for ions is the [[Electron Beam Ion Source]] (EBIS), while for protons, the {{val|200|ul=MeV}} [[linear accelerator]] (Linac) is used. As an example, gold nuclei leaving the EBIS have a kinetic energy of {{val|2|u=MeV}} per nucleon and have an electric charge ''Q'' = +32 (32 of 79 electrons stripped from the gold atom). The particles are then accelerated by the Booster Synchrotron to {{val|100|u=MeV}} per nucleon, which injects the projectile now with ''Q'' = +77 into the [[Alternating Gradient Synchrotron]] (AGS), before they finally reach {{val|8.86|u=GeV}} per nucleon and are injected in a ''Q'' = +79 state (no electrons left) into the RHIC storage ring over the AGS-to-RHIC Transfer Line (AtR).
| |
| | |
| To date the types of particle combinations explored at RHIC are {{nowrap|[[proton|p]] + [[proton|p]]}}, {{nowrap|[[deuteron|d]] + [[gold|Au]]}}, {{nowrap|[[copper|Cu]] + [[copper|Cu]]}}, {{nowrap|[[copper|Cu]] + [[gold|Au]]}}, {{nowrap|[[gold|Au]] + [[gold|Au]]}} and {{nowrap|[[uranium|U]] + [[uranium|U]]}}. The projectiles typically travel at a speed of 99.995% of the [[speed of light]]. For {{nowrap|Au + Au}} collisions, the [[center of mass|center-of-mass]] energy is typically {{val|200|u=GeV}} per [[nucleon]]-pair, and was as low as {{val|7.7|u=GeV}} per [[nucleon]]-pair. An average [[luminosity]] of {{val|2|e=26|u=cm<sup>−2</sup>s<sup>−1</sup>}} was targeted during the planning. The current average luminosity of the collider is {{val|30|e=26|u=cm<sup>−2</sup>s<sup>−1</sup>}}, 15 times the design value.<ref name="RHIC Run Overview">{{cite web
| |
| |author=
| |
| |date=
| |
| |title=RHIC Run Overview
| |
| |url=http://www.agsrhichome.bnl.gov/RHIC/Runs/
| |
| |publisher=[[Brookhaven National Laboratory]]
| |
| |accessdate=
| |
| }}</ref>
| |
| The heavy ion luminosity is increased by a factor of 2 through [[stochastic cooling]].
| |
| <ref>
| |
| {{citation
| |
| |author=M. Blaskiewicz, J. M. Brennan, and K. Mernick
| |
| |title=Three-Dimensional Stochastic Cooling in the Relativistic Heavy Ion Collider
| |
| |url=http://prl.aps.org/abstract/PRL/v105/i9/e094801
| |
| |publisher=Phys. Rev. Lett. 105, 094801 (2010).
| |
| }}</ref>
| |
| | |
| One unique characteristic of RHIC is its capability to collide polarized protons. RHIC holds the record of highest energy polarized protons. Polarized protons are injected into RHIC and preserve this state throughout the energy ramp. This is a difficult task that can only be accomplished with the aid of [[Siberian snake]]s (in RHIC a chain 4 helical [[dipole]] magnets).<ref>
| |
| {{cite journal
| |
| |author=
| |
| |date=22 March 2002
| |
| |title=Snake charming induces spin-flip
| |
| |url=http://www.cerncourier.com/main/article/42/3/2
| |
| |journal=[[CERN Courier]]
| |
| |volume=42 |issue=3 |page=2
| |
| |accessdate=2010-02-16
| |
| }}</ref>
| |
| Run-9 achieved center-of-mass energy of {{val|500|u=GeV}} on 12 February 2009.<ref>
| |
| {{cite web
| |
| |author=
| |
| |date=
| |
| |title=RHIC Run-9
| |
| |url=http://www.agsrhichome.bnl.gov/AP/Spin2009/
| |
| |publisher=[[Brookhaven National Laboratory]]/[[Alternating Gradient Synchrotron]]
| |
| |accessdate=2010-02-16
| |
| }}</ref>
| |
| In Run-13 the average {{nowrap|[[proton|p]] + [[proton|p]]}} luminosity of the collider reached {{val|160|e=30|u=cm<sup>−2</sup>s<sup>−1</sup>}}, with a time and intensity averaged polarization of 52%.<ref name="RHIC Run Overview"/>
| |
| | |
| The AC dipoles have been also used in non-linear machine diagnostics for the first time in RHIC.<ref>
| |
| {{cite journal
| |
| |author=R. Tomás
| |
| |year=2005
| |
| |title=Measurement of global and local resonance terms
| |
| |journal=[[Physical Review Special Topics: Accelerators and Beams]]
| |
| |volume=8 |issue=2 |page=024001
| |
| |doi=10.1103/PhysRevSTAB.8.024001
| |
| |bibcode = 2005PhRvS...8b4001T
| |
| |author-separator=,
| |
| |display-authors=1
| |
| |last2=Bai
| |
| |first2=M.
| |
| |last3=Calaga
| |
| |first3=R.
| |
| |last4=Fischer
| |
| |first4=W.
| |
| |last5=Franchi
| |
| |first5=A.
| |
| |last6=Rumolo
| |
| |first6=G. }}</ref>
| |
| | |
| ==The experiments==
| |
| | |
| There are two [[detector]]s continuing to operate at RHIC: [[STAR detector|STAR]] (6 o'clock, and near the AGS-to-RHIC Transfer Line) and [[PHENIX detector|PHENIX]] (8 o'clock). PHOBOS (10 o'clock) completed its operation in 2005, and BRAHMS (2 o'clock) in 2006.
| |
| | |
| Among the two larger detectors, [[STAR detector|STAR]] is aimed at the detection of [[hadron]]s with its system of [[time projection chamber]]s covering a large [[solid angle]] and in a conventionally generated solenoidal [[magnetic field]], while [[PHENIX detector|PHENIX]] is further specialized in detecting rare and electromagnetic particles, using a partial coverage detector system in a superconductively generated axial magnetic field. The smaller detectors have larger [[pseudorapidity]] coverage, PHOBOS has the largest [[pseudorapidity]] coverage of all detectors, and tailored for bulk particle multiplicity measurement, while BRAHMS is designed for momentum spectroscopy, in order to study the so-called "small-''x''" and saturation physics. There is an additional experiment, PP2PP (now part of STAR), investigating [[spin (physics)|spin]] dependence in p + p [[scattering]].<ref>[http://www.rhic.bnl.gov/pp2pp/ The pp2pp Experiment]. Rhic.bnl.gov. Retrieved on 2013-09-18.</ref>
| |
| | |
| The spokespersons for each of the experiments are:
| |
| *'''STAR''': Nu Xu ([[Lawrence Berkeley Laboratory]], [http://www.lbl.gov/nsd Nuclear Science Division])
| |
| *'''PHENIX''': [[Barbara Jacak]] ([[Stony Brook University]], [http://www.physics.sunysb.edu/Physics/ Department of Physics and Astronomy])
| |
| *'''PP2PP''': Włodek Guryn ([[Brookhaven National Laboratory]], [http://www.bnl.gov/physics/ Physics Department])
| |
| | |
| ==Current results==
| |
| ''For a complementary discussion, see also [[quark-gluon plasma]]''.
| |
| | |
| For the experimental objective of creating and studying the quark-gluon plasma, RHIC has the unique ability to provide baseline measurements for itself. This consists of the both lower energy and also lower [[mass number]] projectile combinations that do not result in the density of 200 GeV Au + Au collisions, like the p + p and d + Au collisions of the earlier runs, and also Cu + Cu collisions in Run-5.
| |
| | |
| Using this approach, important results of the measurement of the hot QCD matter created at RHIC are:<ref>[http://www.physicstoday.org/vol-56/iss-10/p48.html T. Ludlam & L. McLerran, Phys. Today '''October 2003''', 48 (2003).]</ref>
| |
| | |
| * '''Collective anisotropy, or [[elliptic flow]].''' The [[multiplicity (chemistry)|multiplicity]] of the particles' [[bulk]]{{Disambiguation needed|date=June 2011}} with lower [[momentum|momenta]] exhibits a dependency as <math>dn/d\phi \propto 1 + 2 v_2(p_\mathrm{T}) \cos 2 \phi</math> (''p''<sub>T</sub> is the transverse momentum, <math>\phi</math> angle with the reaction plane). This is a direct result of the elliptic shape of the nucleus overlap region during the collision and [[hydrodynamics|hydrodynamical]] property of the matter created.
| |
| | |
| * '''[[Jet (particle physics)|Jet]] quenching.''' In the heavy ion collision event, scattering with a high transverse ''p''<sub>T</sub> can serve as a probe for the hot QCD matter, as it loses its energy while traveling through the medium. Experimentally, the quantity ''R<sub>AA</sub>'' (''A'' is the mass number) being the quotient of observed jet yield in ''A'' + ''A'' collisions and ''N''<sub>bin</sub> × yield in p + p collisions shows a strong damping with increasing ''A'', which is an indication of the new properties of the hot QCD matter created.
| |
| | |
| * '''[[Color glass condensate]] [[saturation (chemistry)|saturation]].''' The Balitsky–Fadin–Kuraev–Lipatov (BFKL) dynamics<ref>L. N. Lipatov, Sov. J. Nucl. Phys. '''23''', 338 (1976).</ref> which are the result of a resummation of large logarithmic terms in ''Q''² for deep inelastic scattering with small Bjorken-''x'', saturate at a unitarity limit <math>Q_s^2 \propto \langle N_\mathrm{part} \rangle/2</math>, with ''N''<sub>part</sub>/2 being the number of participant nucleons in a collision (as opposed to the number of binary collisions). The observed charged multiplicity follows the expected dependency of <math>n_\mathrm{ch}/A \propto 1/\alpha_s(Q_s^2)</math>, supporting the predictions of the [[color glass condensate]] model. For a detailed discussion, see e.g. Kharzeev ''et al.'';<ref>[http://arxiv.org/abs/hep-ph/0210332 D. Kharzeev ''et al.'', Phys. Lett. B '''561''', 93 (2002).]</ref> for an overview of color glass condensates, see e.g. Iancu & Venugopalan.<ref>[http://arxiv.org/abs/hep-ph/0303204 E. Iancu & R. Venugopalan, in ''Quark Gluon Plasma 3'', edited by R. C. Hwa & X.-N. Wang, (World Scientific, Singapore, 2003), p. 249.]</ref>
| |
| | |
| * '''Particle ratios.''' The particle ratios predicted by statistical models allow the calculation of parameters such as the temperature at chemical freeze-out ''T''<sub>ch</sub> and hadron chemical potential <math>\mu_B</math>. The experimental value ''T''<sub>ch</sub> varies a bit with the model used, with most authors giving a value of 160 MeV < ''T''<sub>ch</sub> < 180 MeV, which is very close to the expected QCD phase transition value of approximately 170 MeV obtained by lattice QCD calculations (see e.g. Karsch<ref>[http://arxiv.org/abs/hep-lat/0106019 F. Karsch, in ''Lectures on Quark Matter'', Lect. Notes Phys. 583 (Springer, Berlin, 2002), p. 209.]</ref>).
| |
| | |
| While in the first years, theorists were eager to claim that RHIC has discovered the quark-gluon plasma (e.g. Gyulassy & McLarren<ref>[http://arxiv.org/abs/nucl-th/0405013 M. Gyulassy & L. McLarren, Nucl. Phys. A '''750''', 30 (2005).]</ref>), the experimental groups were more careful not to jump to conclusions, citing various variables still in need of further measurement.<ref>[http://www.bnl.gov/discover/Spring_04/RHIC_1.asp K. McNulty Walsh, "Latest RHIC Results Make News Headlines at Quark Matter 2004", ''Discover Brookhaven'' '''2:1''', 14–17 (2004).]</ref> The present results shows that the matter created is a fluid with a viscosity near the quantum limit, but is unlike a weakly interacting plasma (a widespread yet not quantitatively unfounded belief on how quark gluon plasma looks).
| |
| | |
| A recent overview of the physics result is provided by the [http://www.phenix.bnl.gov/WWW/info/comment/ RHIC Experimental Evaluations 2004], a community-wide effort of RHIC experiments to evaluate the current data in the context of implication for formation of a new state of matter.<ref>[http://arxiv.org/abs/nucl-ex/0410020 I. Arsene ''et al.'' (BRAHMS collaboration), Nucl. Phys. A '''757''' 1, (2005);] [http://arxiv.org/abs/nucl-ex/0410003 K. Adcox ''et al.'' (PHENIX Collaboration), Nucl. Phys. A '''757''', 184 (2005);] [http://arxiv.org/abs/nucl-ex/0410022 B. B. Back ''et al.'' (PHOBOS Collaboration), Nucl. Phys. A '''757''', 28 (2005);] [http://arxiv.org/abs/nucl-ex/0501009 J. Adams ''et al.'' (STAR Collaboration), Nucl. Phys. A '''757''', 102 (2005).]</ref> These results are from the first three years of data collection at RHIC.
| |
| | |
| New results were published in [[Physical Review Letters]] on February 16, 2010, stating the discovery of the first hints of [[symmetry transformations]], and that the observations may suggest that bubbles formed in the aftermath of the collisions created in the RHIC may break [[Parity (physics)|parity symmetry]], which normally characterizes [[color charge|interactions]] between [[quarks]] and [[gluons]].<ref name=symmetry>
| |
| {{cite web
| |
| |author=K. Melville
| |
| |date=16 February 2010
| |
| |title=Mirror Symmetry Broken at 7 Trillion Degrees
| |
| |url=http://www.scienceagogo.com/news/20100115233339data_trunc_sys.shtml
| |
| |work=Science a Go Go
| |
| |accessdate=2010-02-16
| |
| }}</ref><ref>
| |
| {{cite news
| |
| |author=D. Overbye
| |
| |date=15 February 2010
| |
| |title=In Brookhaven Collider, Scientists Briefly Break a Law of Nature
| |
| |url=http://www.nytimes.com/2010/02/16/science/16quark.html
| |
| |work=[[New York Times]]
| |
| |accessdate=2010-02-16
| |
| }}</ref>
| |
| | |
| The RHIC physicists announced new temperature measurements for these experiments of up to 4 trillion kelvins, the highest temperature ever achieved in a laboratory.<ref>[http://www.bnl.gov/bnlweb/pubaf/pr/PR_display.asp?prID=1074 Perfect Liquid Hot Enough to be Quark Soup]</ref> It is described as a recreation of the conditions that existed during the [[birth of the Universe]].<ref name=temperature>
| |
| {{cite web
| |
| |author=D. Vergano
| |
| |date=16 February 2010
| |
| |title=Scientists Re-create High Temperatures from Big Bang
| |
| |url=http://www.usatoday.com/tech/science/2010-02-16-RHIC16_ST_N.htm
| |
| |work=[[USA Today]]
| |
| |accessdate=2010-02-16
| |
| }}</ref>
| |
| | |
| ==The future==
| |
| RHIC began operation in 2000 and until November 2010 was the most powerful heavy-ion collider in the world. The [[Large Hadron Collider|Large Hadron Collider (LHC)]] of [[CERN]], while used mainly for colliding protons, operates with heavy ions for about one month per year. LHC will eventually operate 28 times higher ion energies, although current LHC operation is at half this energy. As of 2012 RHIC and the LHC are the only operating hadron colliders in the world.
| |
| | |
| Due to the longer operating time per year, a greater number of colliding ion species and collision energies can be studied at RHIC. In addition and unlike the LHC, RHIC is able to accelerate spin polarized protons, which would leave RHIC as the world's highest energy accelerator for studying spin-polarized proton structure.
| |
| | |
| A planned major upgrade is '''eRHIC''': The construction of a 10 GeV high intensity electron/positron beam facility, allowing electron-ion collisions. At least one new detector will have to be built to study the collisions. A recent review is given by A. Deshpande ''et al.''.<ref>[http://arxiv.org/hep-ph/0506148 A. Deshpande ''et al.'', Ann. Rev. Nucl. Part. Sci. '''55''', 165 (2005).]</ref>
| |
| | |
| In October 2006, then Interim Director of BNL, Sam Aronson, has contested the claim in a [[Physics Today]] report that "''[[Tevatron]] is unlikely to outlive the decade. Neither is ... the Relativistic Heavy Ion Collider''", referring to a report of the [[United States National Research Council|National Research Council]].<ref>[http://www.physicstoday.org/vol-59/iss-10/p15a.html S. Aronson, Phys. Today, October 2006, 15.]</ref>
| |
| | |
| ==Possible closure under flat nuclear science budget scenarios==
| |
| In late 2012, the [http://science.energy.gov/np/nsac/ Nuclear Science Advisory Committee (NSAC)] was asked to advise the Department of Energy's Office of Science and the National Science Foundation how to implement the nuclear science long range plan written in 2007, if future nuclear science budgets continue to provide no growth over the next four years. In a narrowly decided vote, the NSAC committee showed a slight preference, based on non-science related considerations,<ref>{{cite web |title=NSAC Charges / Reports |publisher=Nuclear Science Advisory Committee |url=http://science.energy.gov/np/nsac/reports/}}</ref> for shutting down RHIC rather than canceling the construction of the Facility for Rare Ion Beams (FRIB).<ref>{{cite journal |last1=Matson |first1=John |last2= |first2= |date=January 31, 2013 |title=Decelerating American Physics: Panel Advises Shutdown of Last U.S. Collider |journal=[[Scientific American]] |volume= |issue= |pages= |publisher= |doi= |url=http://www.scientificamerican.com/article.cfm?id=tribble-panel-rhic-closure |accessdate=February 2, 2013}}</ref>
| |
| | |
| ==Critics of high energy experiments==
| |
| {{See also|Safety of particle collisions at the Large Hadron Collider}}
| |
| {{Wikinews|Possible black hole created in US}}
| |
| Before RHIC started operation, critics postulated that the extremely high energy could produce catastrophic scenarios,<ref>[http://www.findarticles.com/p/articles/mi_m2843/is_3_24/ai_62102225 T. D. Gutierrez, "Doomsday Fears at RHIC," Skeptical Inquirer '''24''', 29 (May 2000)]</ref>
| |
| such as creating a [[black hole]], a transition into a different [[quantum mechanics|quantum mechanical]] [[vacuum state|vacuum]] (see [[false vacuum]]), or the creation of [[strange matter]] that is more stable than ordinary [[matter]]. These hypotheses are complex, but many predict that the [[Earth]] would be destroyed in a time frame from seconds to millennia, depending on the theory considered. However, the fact that objects of the Solar System (e.g., the [[Moon]]) have been bombarded with [[cosmic ray|cosmic particles]] of significantly higher energies than that of RHIC and other man-made colliders for billions of years, without any harm to the Solar System, were among the most striking arguments that these hypotheses were unfounded.<ref name="jaffe"/>
| |
| | |
| {{Wikinews|Fireball generated in U.S. laboratory resembles black hole}}
| |
| The other main controversial issue was a demand by critics {{Citation needed|date=January 2008}} for [[physicist]]s to reasonably exclude the [[probability]] for such a catastrophic scenario. Physicists are unable to demonstrate experimental and [[astrophysics|astrophysical]] constraints of zero probability of catastrophic events, nor that tomorrow Earth will be struck with a "[[Doomsday event|doomsday]]" [[cosmic ray]] (they can only calculate an upper limit for the likelihood). The result would be the same destructive scenarios described above, although obviously not caused by humans. According to this argument of upper limits, RHIC would still modify the chance for the Earth's survival by an infinitesimal amount.
| |
| | |
| Concerns were raised in connection with the RHIC particle accelerator, both in the media<ref>{{cite journal |journal=[[New Scientist]] |date=28 August 1999 |title=A Black Hole Ate My Planet |url=http://www.newscientist.com/article/mg16322014.700-a-black-hole-ate-my-planet.html |last=Matthews |first=Robert |authorlink=Robert Matthews (scientist)}}</ref><ref name="End Day">{{Cite episode |serieslink=Horizon (BBC TV series) |series=Horizon |titlelink=End Day |title=End Day |network=BBC |year=2005}}</ref> and in the popular science media.<ref>W. Wagner, "Black holes at Brookhaven?" and reply by F. Wilzcek, Letters to the Editor, Scientific American July 1999</ref> The risk of a doomsday scenario was indicated by [[Martin Rees]], with respect to the RHIC, as being at least a 1 in 50,000,000 chance.<ref>Cf. [[Brookhaven National Laboratory|Brookhaven]] Report mentioned by [[Martin Rees, Baron Rees of Ludlow|Rees, Martin]] (Lord), ''Our Final Century: Will the Human Race Survive the Twenty-first Century?'', U.K., 2003, ISBN 0-465-06862-6; note that the mentioned "1 in 50 million" chance is disputed as being a misleading and played down probability of the serious risks (Aspden, U.K., 2006)</ref> With regards to the production of [[strangelet]]s, [[Frank Close]], professor of physics at the [[University of Oxford]], indicates that "the chance of this happening is like you winning the major prize on the lottery 3 weeks in succession; the problem is that people believe it is possible to win the lottery 3 weeks in succession."<ref name="End Day"/> After detailed studies, scientists reached such conclusions as "beyond reasonable doubt, heavy-ion experiments at RHIC will not endanger our planet"<ref>A. Dar, A. De Rujula, U. Heinz, "Will relativistic heavy ion colliders destroy our planet?", Phys. Lett. B470:142–148 (1999) [http://www.arxiv.org/abs/hep-ph/9910471 arXiv:hep-ph/9910471]</ref> and that there is "powerful empirical evidence against the possibility of dangerous strangelet production."<ref>W. Busza, R. Jaffe, J. Sandweiss, F. Wilczek, "Review of speculative 'disaster scenarios' at RHIC", Rev. Mod. Phys.72:1125–1140 (2000) [http://www.arxiv.org/abs/hep-ph/9910333 arXiv:hep-ph/9910333]</ref>
| |
| | |
| The debate started in 1999 with an exchange of letters in [[Scientific American]] between Walter L. Wagner,<ref>Wagner is a lawyer and former physics lab technician. In 1975, he worked on a project that claimed to discover a [[magnetic monopole]] in cosmic ray data ("Evidence for the Detection of a Moving Magnetic Monopole", Physical Review Letters, Vol. 35, (1975)). That claim was later withdrawn in 1978 ("Further Measurements and Reassessment of the Magnetic Monopole Candidate", Physical Review D18: 1382–1421 (1978))</ref> and [[Frank Wilczek|F. Wilczek]],<ref>Wilczek is noted for his work on quarks, for which he subsequently was awarded the Nobel Prize</ref> [[Institute for Advanced Study]], in response to a previous article by M. Mukerjee.<ref>M. Mukerjee, [http://www.sciam.com Scientific American] '''280:March''', 60 (1999). The Wagner and Wilczek letters follow in the July issue (vol. 281 no. 1), p. 8.</ref> The media attention unfolded with an article in [[United Kingdom|U.K.]] [[The Sunday Times (UK)|Sunday Times]] of July 18, 1999 by J. Leake,<ref name="JLeake18July1999">[http://www.wisdomofsolomon.com/bigbang.html Sunday Times, 18 July 1999.]</ref> closely followed by articles in the U.S. media.<ref>e.g. [http://web.archive.org/web/20031005104321/abcnews.go.com/sections/tech/FredMoody/moody990914.html ABCNEWS.com], from the [[Internet Archive]].</ref> The controversy mostly ended with the report of a [[committee]] convened by the [[Board of Directors|director]] of Brookhaven National Laboratory, [[John Marburger|J. H. Marburger]], ostensibly ruling out the catastrophic scenarios depicted.<ref name="jaffe">[http://arxiv.org/abs/hep-ph/9910333 R. Jaffe ''et al.'', Rev. Mod. Phys. '''72''', 1125–1140 (2000).]</ref> However, the report left open the possibility that relativistic cosmic ray impact products might behave differently while transiting earth compared to "at rest" RHIC products; and the possibility that the qualitative difference between high-E proton collisions with earth or the moon might be different than gold on gold collisions at the RHIC. Wagner tried subsequently to stop full energy collision at RHIC by filing [[Federal government of the United States|Federal]] lawsuits in [[San Francisco]] and [[New York]], but without success.<ref>e.g. [http://www.msnbc.msn.com/id/3077374/ MSNBC, June 14, 2000.]</ref> The New York suit was dismissed on the technicality that the San Francisco suit was the preferred forum. The San Francisco suit was dismissed, but with leave to refile if additional information was developed and presented to the court.<ref>United States District Court, Eastern District of New York, Case No. 00CV1672, Walter L. Wagner vs. Brookhaven Science Associates, L.L.C. (2000); United States District Court, Northern District of California, Case No. C99-2226, Walter L. Wagner vs. U.S. Department of Energy, et al. (1999)</ref>
| |
| | |
| On March 17, 2005, the [[BBC]] published an article<ref>[http://news.bbc.co.uk/1/hi/sci/tech/4357613.stm BBC, 17 March 2005.]</ref> implying that researcher [[Horaţiu Năstase]] believes black holes have been created at RHIC. However, the original papers of H. Năstase<ref>[http://arxiv.org/abs/hep-th/0501068 H. Nastase, hep-th/0501068 (2005).]</ref> and the [[New Scientist]] article<ref>[http://www.newscientist.com/channel/fundamentals/mg18524915.400 E. S. Reich, New Scientist '''185:2491''', 16 (2005).]</ref> cited by the BBC state that the correspondence of the hot dense [[QCD matter]] created in RHIC to a black hole is only in the sense of a correspondence of [[Quantum chromodynamics|QCD]] scattering in [[Minkowski space]] and scattering in the ''AdS''<sub>5</sub> × ''X''<sub>5</sub> space in [[AdS/CFT]]; in other words, it is similar mathematically. Therefore, RHIC collisions might be described by mathematics relevant to theories of [[quantum gravity]] within AdS/CFT, but the described physical phenomena are not the same.
| |
| | |
| ==Financial information==
| |
| The RHIC project is sponsored by the [[United States Department of Energy]], Office of [[Science]], Office of [[Nuclear physics|Nuclear Physics]].<ref>[http://www.er.doe.gov/np/ U.S. Department of Energy, Office of Science, Office of Nuclear Physics]</ref> It had a line-item budget of 616.6 million [[U.S. dollar]]s.<ref>[http://dx.doi.org/10.1016/S0168-9002(02)01937-X M. Harrison, T. Ludlam, & S. Ozaki, Nucl. Instr. Meth. Phys. Res. A '''499:2–3''', 235 (2003).]</ref> The annual operational budgets were:<ref>[http://www.cfo.doe.gov/budget/ U.S. Department of Energy, Office of Budget]</ref>
| |
| * [[fiscal year]] 2005: 131.6 million U.S. dollars
| |
| * fiscal year 2006: 115.5 million U.S. dollars
| |
| * fiscal year 2007, requested: 143.3 million U.S. dollars
| |
| The total investment by 2005 is approximately 1.1 billion U.S. dollars. Though operation under the fiscal year 2006 federal budget cut<ref>e.g. [http://www.aip.org/fyi/2005/168.html FYI, November 22, 2005;] [http://select.nytimes.com/gst/abstract.html?res=F20713F73C550C748EDDA80994DD404482 New York Times, November 27, 2005.]</ref> was uncertain, a key portion of the operational cost (13 million U.S. dollars) was contributed privately by a group close to [[Renaissance Technologies]] of [[East Setauket, New York]].<ref>e.g. [http://www.aps.org/apsnews/0306/030604.cfm APS News Online, March 2006;] [http://www.aip.org/fyi/2006/006.html FYI, November 22, 2005.]</ref>
| |
| | |
| ==RHIC in fiction==
| |
| * The novel ''Cosm'' (ISBN 0-380-79052-1) by the American author [[Gregory Benford]] takes place at RHIC. The [[science fiction]] setting describes the main character Alicia Butterworth, a physicist at the BRAHMS experiment, and a new [[universe]] being created in RHIC by accident, while running with [[uranium]] ions.<ref>[http://www.bnl.gov/bnlweb/pubaf/bulletin/1998/bb022098.pdf Brookhaven Bulletin '''52''', 8 (1998)], p. 2.</ref>
| |
| | |
| * The [[zombie apocalypse]] novel ''[[The Rising (Keene novel)|The Rising]]'' by the American author [[Brian Keene]] referenced the media concerns of activating the RHIC raised by the article in [[The Sunday Times (UK)|The Sunday Times]] of July 18, 1999 by J. Leake,.<ref name="JLeake18July1999" /> As revealed very early in the story, side effects of the collider experiments of the RHIC (located at "Havenbrook National Laboratories") were the cause of the zombie uprising in the novel and its sequel ''[[City of the Dead (novel)|City of the Dead]]''.
| |
| | |
| * The novel ''[http://karldrinkwater.blogspot.com/p/cold-fusion-2000.html Cold Fusion 2000]'' by the UK author Karl Drinkwater also referenced the media concerns of activating the RHIC raised by the article in [[The Sunday Times (UK)|The Sunday Times]] of July 18, 1999 by J. Leake,.<ref name="JLeake18July1999" /> The novel was set in the year 2000 and the first experiments of the RHIC tie into the plot by creating a strange situation that allows the physics-obsessed protagonist to meet his ex lover.<ref>[http://karldrinkwater.blogspot.com/2013/01/cf2k-faqs.html Karl's Writing Blog: CF2K - F.A.Q.s]. Karldrinkwater.blogspot.com (2013-01-14). Retrieved on 2013-09-18.</ref>
| |
| | |
| ==See also==
| |
| * [[ISABELLE|The ISABELLE Project]]
| |
| * [[Large Hadron Collider]]
| |
| | |
| ==References==
| |
| {{reflist|2}}
| |
| | |
| ==Further reading==
| |
| *{{cite journal
| |
| |author=M. Harrison, T. Ludlam and S. Ozaki (eds)
| |
| |year=2003
| |
| |title=The Relativistic Heavy Ion Collider Project: RHIC and its Detectors
| |
| |url=http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235314%232003%23995009997%23459310%23FLA%23&_cdi=5314&_pubType=J&_auth=y&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=0a6c6433f261a636ae8150534e4fc6ab
| |
| |journal=[[Nuclear Instruments and Methods in Physics Research A]]
| |
| |volume=499 |issue=2–3 |pages=235–880
| |
| |bibcode = 2003NIMPA.499..235H |doi = 10.1016/S0168-9002(02)01937-X }} Preprints are available at
| |
| :* [http://www4.rcf.bnl.gov/brahms/WWW/publications.html BRAHMS]
| |
| :* [http://www.phenix.bnl.gov/techpapers.html PHENIX]
| |
| :* [http://www.phobos.bnl.gov/Publications/Technical/phobos_technical_publications.htm PHOBOS]
| |
| :* [http://www.star.bnl.gov/STAR/publications/technical_publications STAR]
| |
| | |
| ==External links==
| |
| *[http://www.bnl.gov/cad/ Brookhaven National Laboratory Collider-Accelerator Department]
| |
| *[http://www.bnl.gov/rhic/ Relativistic Heavy Ion Collider]
| |
| *[http://maps.google.com/maps?z=15&ll=40.883475,-72.875876&spn=0.018624,0.043259&t=k&om=1 Relativistic Heavy Ion Collider at Google Maps]
| |
| *[http://www.agsrhichome.bnl.gov/RHIC/Runs/ RHIC Run Overview]
| |
| | |
| {{Coord|40|53|2|N|72|52|33|W|region:US-NY_type:landmark|display=title}}
| |
| | |
| [[Category:Particle physics facilities]]
| |
| [[Category:Quark matter]]
| |
| [[Category:Brookhaven National Laboratory]]
| |