Evidence of Final-State Suppression of High-p_T Hadrons in Au + Au Collisions Using d + Au Measurements at RHIC

Transverse momentum spectra of charged hadrons with ${p_{T} <}$ 6 GeV/c have been measured near mid-rapidity (0.2 $< \eta <$ 1.4) by the PHOBOS experiment at RHIC in Au + Au and d + Au collisions at ${\sqrt{s_{_{NN}}} = \rm {200 GeV}}$. The spectra for different collision centralities are compared to ${p + \bar{p}}$ collisions at the same energy. The resulting nuclear modification factor for central Au + Au collisions shows evidence of strong suppression of charged hadrons in the high-$p_{T}$ region (${>2}$ GeV/c). In contrast, the d + Au nuclear modification factor exhibits no suppression of the high-$p_{T}$ yields. These measurements suggest a large energy loss of the high-$p_{T}$ particles in the highly interacting medium created in the central Au + Au collisions. The lack of suppression in d + Au collisions suggests that it is unlikely that initial state effects can explain the suppression in the central Au + Au collisions.Comment: 3 pages, 4 figures, International Europhysics Conference on High Energy Physics EPS (July 17th-23rd 2003) in Aachen, German

Cost savings from a policy to diagnose and prevent transmission of adenoviral conjunctivitis in employees of a large academic medical center

IMPORTANCE Adenoviral conjunctivitis is highly contagious, can be associated with systemic infections, and can cause chronic visual impairment. It accounts for a large proportion of acute conjunctivitis. Outbreaks of epidemic keratoconjunctivitis (EKC) are costly in terms of productivity loss from work furloughs and spread to patients and have resulted in clinic and departmental closures. OBJECTIVE To examine the institutional cost savings of a policy to diagnose adenoviral conjunctivitis and triage and furlough medical center employees with this condition to prevent outbreaks. DESIGN, SETTING, AND PARTICIPANTS This quality improvement study assessed Johns Hopkins Medicine employees with red eye from November 1, 2011, through October 31, 2018, who were triaged at the occupational health clinic whose conditions were diagnosed using polymerase chain reaction (PCR) validated for adenoviral conjunctivitis. INTERVENTIONS Only employees with positive PCR test results were furloughed, with furlough length tailored to subtype (a minimum of 2 weeks for EKC and 1 week otherwise). MAIN OUTCOMES AND MEASURES Total number of furloughs avoided and cost savings associated with reducing unnecessary furloughs. RESULTS Of 2142 employees with red eye, 1520 (71.0%) underwent PCR testing; 130 (8.6%) had positive adenoviral PCR test results, of whom 41 (31.5%) had EKC. Furloughing 130 employees with positive PCR test results vs furloughing all 1520 employees clinically suspected of having adenoviral conjunctivitis represented an estimated annual savings of $442 073, or$3 094 511 during 7 years. The cost of performing PCR on employees suspected of having adenoviral conjunctivitis was 5.0% of the cost associated with furloughing all employees with red eye. No outbreaks occurred. CONCLUSIONS AND RELEVANCE In this quality improvement study, this policy, notable for development and use of PCR for adenoviral conjunctivitis on a large scale, resulted in substantial cost savings from fewer work furloughs compared with the number of employees who would have been furloughed based on clinical diagnosis. These results may provide impetus for policy adoption by other institutions and for development of a rapid, sensitive, and specific diagnostic test for adenoviral conjunctivitis

Identified particles in Au+Au collisions at sqrt{s_NN} = 200 GeV

The yields of identified particles have been measured at RHIC for Au+Au collisions at sqrt{s_NN} = 200 GeV using the PHOBOS spectrometer. The ratios of antiparticle to particle yields near mid-rapidity are presented. The first measurements of the invariant yields of charged pions, kaons and protons at very low transverse momenta are also shown.Comment: 4 pages, 4 figures, Contribution to Quark Matter 2002, Nantes, France, July 200

Recent Results from PHOBOS at RHIC

The PHOBOS experiment at RHIC has recorded measurements for Au-Au collisions spanning nucleon-nucleon center-of-mass energies from 19.6 GeV to 200 GeV. Global observables such as elliptic flow and charged particle multiplicity provide important constraints on model predictions that characterize the state of matter produced in these collisions. The nearly 4 pi acceptance of the PHOBOS experiment provides excellent coverage for complete flow and multiplicity measurements. Results including beam energy and centrality dependencies are presented and compared to elementary systems.Comment: 4 pages, 4 figures, proceedings from PANIC02 in Osaka, Japa

Universal Behavior of Charged Particle Production in Heavy Ion Collisions

The PHOBOS experiment at RHIC has measured the multiplicity of primary charged particles as a function of centrality and pseudorapidity in Au+Au collisions at sqrt(s_NN) = 19.6, 130 and 200 GeV. Two kinds of universal behavior are observed in charged particle production in heavy ion collisions. The first is that forward particle production, over a range of energies, follows a universal limiting curve with a non-trivial centrality dependence. The second arises from comparisons with pp/pbar-p and e+e- data. N_tot/(N_part/2) in nuclear collisions at high energy scales with sqrt(s) in a similar way as N_tot in e+e- collisions and has a very weak centrality dependence. This feature may be related to a reduction in the leading particle effect due to the multiple collisions suffered per participant in heavy ion collisions.Comment: 4 Pages, 5 Figures, contributed to the Proceedings of Quark Matter 2002, Nantes, France, 18-24 July 200

Search for black holes and other new phenomena in high-multiplicity final states in proton-proton collisions at root s=13 TeV

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Search for heavy resonances decaying into a vector boson and a Higgs boson in final states with charged leptons, neutrinos, and b quarks

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Search for high-mass diphoton resonances in proton-proton collisions at 13 TeV and combination with 8 TeV search

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Measurement of the mass difference between top quark and antiquark in pp collisions at root s=8 TeV

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Search for leptophobic Z ' bosons decaying into four-lepton final states in proton-proton collisions at root s=8 TeV

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