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S S Adler

Publications and source records attributed to S S Adler.

At least 37 records · Page 2Linked to original sources
PubMed2003

Elliptic flow of identified hadrons in Au+Au collisions at sqrt sNN =200 GeV.

The anisotropy parameter (v(2)), the second harmonic of the azimuthal particle distribution, has been measured with the PHENIX detector in Au+Au collisions at sqrt[s(NN)]=200 GeV for identified and inclusive charged particle production at central rapidities (|eta|<0.35) with respect to the reaction plane defined at high rapidities (|eta|=3-4 ). We observe that the v(2) of mesons falls below that of (anti)baryons for p(T)>2 GeV/c, in marked contrast to the predictions of a hydrodynamical model. A quark-coalescence model is also investigated.

Journal Article↗
PubMed2003

Scaling properties of proton and antiproton production in sqrt[s(NN)]=200 GeV Au+Au collisions.

We report on the yield of protons and antiprotons, as a function of centrality and transverse momentum, in Au+Au collisions at sqrt[s(NN)]=200 GeV measured at midrapidity by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider. In central collisions at intermediate transverse momenta (1.5<p(T)<4.5 GeV/c) a significant fraction of all produced particles are protons and antiprotons. They show a centrality-scaling behavior different from that of pions. The pmacr;/pi and p/pi ratios are enhanced compared to peripheral Au+Au, p+p, and e(+)e(-) collisions. This enhancement is limited to p(T)<5 GeV/c as deduced from the ratio of charged hadrons to pi(0) measured in the range 1.5<p(T)<9 GeV/c.

Journal Article↗
PubMed2003

Absence of suppression in particle production at large transverse momentum in sqrt[s(NN)]=200 GeV d+Au collisions.

Transverse momentum spectra of charged hadrons with p(T)<8 GeV/c and neutral pions with p(T)<10 GeV/c have been measured at midrapidity by the PHENIX experiment at BNL RHIC in d+Au collisions at sqrt[s(NN)]=200 GeV. The measured yields are compared to those in p+p collisions at the same sqrt[s(NN)] scaled up by the number of underlying nucleon-nucleon collisions in d+Au. The yield ratio does not show the suppression observed in central Au+Au collisions at RHIC. Instead, there is a small enhancement in the yield of high momentum particles.

Journal Article↗
PubMed2003

Suppressed pi(0) production at large transverse momentum in central Au+Au collisions at sqrt[s(NN)]=200 GeV.

Transverse momentum spectra of neutral pions in the range 1<p(T)<10 GeV/c have been measured at midrapidity by the PHENIX experiment at BNL RHIC in Au+Au collisions at sqrt[s(NN)]=200 GeV. The pi(0) multiplicity in central reactions is significantly below the yields measured at the same sqrt[s(NN)] in peripheral Au+Au and p+p reactions scaled by the number of nucleon-nucleon collisions. For the most central bin, the suppression factor is approximately 2.5 at p(T)=2 GeV/c and increases to approximately 4-5 at p(T) approximately 4 GeV/c. At larger p(T), the suppression remains constant within errors. The deficit is already apparent in semiperipheral reactions and increases smoothly with centrality.

Journal Article↗
PubMed2002

Flow measurements via two-particle azimuthal correlations in Au + Au collisions at sqrt [s(NN)]=130 GeV.

Two-particle azimuthal correlation functions are presented for charged hadrons produced in Au+Au collisions at the Relativistic Heavy Ion Collider (sqrt [s(NN)]=130 GeV). The measurements permit determination of elliptic flow without event-by-event estimation of the reaction plane. The extracted elliptic flow values (v2) show significant sensitivity to both the collision centrality and the transverse momenta of emitted hadrons, suggesting rapid thermalization and relatively strong velocity fields. When scaled by the eccentricity of the collision zone epsilon, the scaled elliptic flow shows little or no dependence on centrality for charged hadrons with relatively low p(T). A breakdown of this epsilon scaling is observed for charged hadrons with pT >1.0 GeV/c.

Journal Article↗
PubMed2002

Measurement of Lambda and Lambda(macro) particles in Au+Au collisions at the square root of S(NN) = 130 GeV.

We present results on the measurement of Lambda and Lambda(macro) production in Au+Au collisions at square root of (S (NN) = 130 GeV with the PHENIX detector at the Relativistic Heavy Ion Collider. The transverse momentum spectra were measured for minimum bias and for the 5% most central events. The Lambda;/Lambda ratios are constant as a function of p(T) and the number of participants. The measured net Lambda density is significantly larger than predicted by models based on hadronic strings (e.g., HIJING) but in approximate agreement with models which include the gluon-junction mechanism.

Journal Article↗
PubMed2002

Net charge fluctuations in Au + Au interactions at sqrt[s(NN)]=130 GeV.

Data from Au + Au interactions at sqrt[s(NN)]=130 GeV, obtained with the PHENIX detector at the Relativistic Heavy-Ion Collider, are used to investigate local net charge fluctuations among particles produced near midrapidity. According to recent suggestions, such fluctuations may carry information from the quark-gluon plasma. This analysis shows that the fluctuations are dominated by a stochastic distribution of particles, but are also sensitive to other effects, like global charge conservation and resonance decays.

Journal Article↗
PubMed2002

Centrality dependence of pi(+/-), K(+/-), p, and (-)p production from sqrt[s(NN)] = 130 GeV Au + Au collisions at RHIC.

Identified pi(+/-), K(+/-), p, and (-)p transverse momentum spectra at midrapidity in sqrt[s(NN)] = 130 GeV Au+Au collisions were measured by the PHENIX experiment at RHIC as a function of collision centrality. Average transverse momenta increase with the number of participating nucleons in a similar way for all particle species. Within errors, all midrapidity particle yields per participant are found to be increasing with the number of participating nucleons. There is an indication that K(+/-), p, and (-)p yields per participant increase faster than the pi(+/-) yields. In central collisions at high transverse momenta (p(T) > or =2 GeV/c), (-)p and p yields are comparable to the pi(+/-) yields.

Journal Article↗
PubMed2002

Transverse-mass dependence of two-pion correlations in Au+Au collisions at square root[s(NN)] = 130 GeV.

Two-pion correlations in square root[s(NN)] = 130 GeV Au+Au collisions at RHIC have been measured over a broad range of pair transverse momentum k(T) by the PHENIX experiment at RHIC. The k(T) dependent transverse radii are similar to results from heavy-ion collisions at square root[s(NN)] = 4.1, 4.9, and 17.3 GeV, whereas the longitudinal radius increases monotonically with beam energy. The ratio of the outwards to sidewards transverse radii (R(out)/R(side)) is consistent with unity and independent of k(T).

Journal Article↗
PubMed2002

Measurement of single electrons and implications for charm production in Au+Au collisions at square root[s(NN)] = 130 GeV.

Transverse momentum spectra of electrons from Au+Au collisions at square root[s(NN)] = 130 GeV have been measured at midrapidity by the PHENIX experiment at the Relativistic Heavy Ion Collider. The spectra show an excess above the background from photon conversions and light hadron decays. The electron signal is consistent with that expected from semileptonic decays of charm. The yield of the electron signal dN(e)/dy for p(T) > 0.8 GeV/c is 0.025+/-0.004(stat)+/-0.010(syst) in central collisions, and the corresponding charm cross section is 380+/-60(stat)+/-200(syst) microb per binary nucleon-nucleon collision.

Journal Article↗
PubMed2001

Suppression of hadrons with large transverse momentum in central Au+Au collisions at root square[s(NN)] = 130 GeV.

Transverse momentum spectra for charged hadrons and for neutral pions in the range 1 GeV/c<p(T)<5 GeV/c have been measured by the PHENIX experiment at RHIC in Au+Au collisions at root square[s(NN)] = 130 GeV. At high p(T) the spectra from peripheral nuclear collisions are consistent with scaling the spectra from p+p collisions by the average number of binary nucleon-nucleon collisions. The spectra from central collisions are significantly suppressed when compared to the binary-scaled p+p expectation, and also when compared to similarly binary-scaled peripheral collisions, indicating a novel nuclear-medium effect in central nuclear collisions at RHIC energies.

Journal Article↗
PubMed2001

Measurement of the midrapidity transverse energy distribution from square root of [(s)NN] = 130 GeV Au + Au collisions at RHIC.

The first measurement of energy produced transverse to the beam direction at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory is presented. The midrapidity transverse energy density per participating nucleon rises steadily with the number of participants, closely paralleling the rise in charged-particle density, such that / remains relatively constant as a function of centrality. The energy density calculated via Bjorken's prescription for the 2% most central Au+Au collisions at square root[s(NN)] = 130 GeV is at least epsilon(Bj) = 4.6 GeV/fm(3), which is a factor of 1.6 larger than found at sqrt[s(NN)] = 17.2 GeV ( Pb+Pb at CERN).

Journal Article↗
PubMed2001

Centrality dependence of charged particle multiplicity in Au-Au collisions at square root of (s)NN = 130 GeV.

We present results for the charged-particle multiplicity distribution at midrapidity in Au-Au collisions at square root of [s(NN)] = 130 GeV measured with the PHENIX detector at RHIC. For the 5% most central collisions we find dN(ch)/d eta(vertical line eta = 0) = 622+/-1(stat)+/-41(syst). The results, analyzed as a function of centrality, show a steady rise of the particle density per participating nucleon with centrality.

Journal Article↗
PubMed1995

Tandem peripheral blood progenitor cell transplants as initial therapy for metastatic breast cancer.

PURPOSE: To investigate the use of two sequential courses of high-dose chemotherapy and peripheral blood progenitor cell (PBPC) transplant as initial therapy for patients with untreated metastatic breast cancer. The goal of the study was to maximize treatment intensity through the use of two non-cross-resistant regimens, each equal in intensity to that used in single transplants. METHODS: PBPC were collected after a course of granulocyte colony-stimulating factor (G-CSF) only or of cyclophosphamide, etoposide, and G-CSF. The first transplant regimen consisted of thiotepa (600 mg/m2), cyclophosphamide (6000 mg/m2), and carboplatin (800 mg/m2). After recovery from the first transplant, responding patients received a second course of therapy consisting of busulfan (16 mg/kg) and etoposide (60 mg/kg). RESULTS: Forty-four patients were enrolled. Five patients did not proceed to transplantation due to tumor progression during PBPC mobilization. Five patients achieved complete response after the first transplant, and 14 were in complete remission at the end of the therapy. Six patients remain free of disease after a median followup of 22 months (range 12-27+ months). The 2-year event-free survival for complete responders is 25.4% (standard error 14.4%). Engraftment was prompt, with a median of 8 and 13 days, respectively, to reach a neutrophil count of 500/mm3 and a platelet count of 50,000/mm3. As a result of the gastrointestinal toxicity of the first course, the median interval between transplants was 68 days. The toxicities of the second transplant course were principally hepatic and muco-cutaneous. Hepatic veno-occlusive disease occurred in 12 patients and was a contributor to the death of three. CONCLUSIONS: Rapid hematologic recovery achieved with PBPC made possible the administration of two courses of high-dose chemotherapy without compromising the intensity of either transplant regimen. The adverse effects of the second course, however, were substantially higher than predicted. The outcome of patients achieving a complete response is promising. Overall, the antitumor benefit of this approach in patients with previously untreated metastatic disease was not superior to that achieved with single transplants in patients responding to standard-dose chemotherapy.

Adult↗
PubMed1994

Comparisons of intellectual performance among children with psychiatric disorders.

The intellectual performances of children with a variety of psychiatric disorders were examined and compared with the findings from a similar study by Hodges and Plow (1990). Mean IQ scores were in the average range for both study samples, and no significant differences were found in WISC-R summary scores. Nevertheless, the Hodges and Plow findings were only partially corroborated. They observed, for instance, a relative deficit in verbal abilities for conduct-disordered children and lower IQ scores for children with anxiety disorders vs. children with all other disorders. Our replication study found no significant differences among the disorder groups for any of the scores examined. Possible explanations for the divergence in findings are discussed.

Anxiety Disorders↗
PubMed1994

Intellectual competence of children who are beginning inpatient and day psychiatric treatment.

Intellectual abilities of 300 children with serious emotional disorders, referred to either psychiatric day- or inpatient-hospital treatment, were compared. Comparisons also were made to WISC-R standardization data. The findings indicated that children referred to inpatient settings were similar in intellectual competency to children in day treatment. Also, children with serious emotional disorders did not appear to differ strongly in clinically meaningful ways from the WISC-R standardization sample, a finding that replicates results of other investigators. Three distinct, clinically useful profiles emerged from a cluster analysis of the total group that may be practical in planning educational and therapeutic interventions in treatment settings for seriously disturbed children. The profiles underscored the wide range of intellectual abilities represented among these children.

Ambulatory Care↗
PubMed1994

Treatment of metastatic breast cancer with a split-course high-dose chemotherapy regimen and autologous bone marrow transplantation.

PURPOSE: We investigated the role of high-dose chemotherapy and autologous bone marrow transplantation (ABMT) as the initial systemic treatment in patients with hormone-unresponsive metastatic breast cancer. We studied a regimen involving a split-course schedule using sequential administration of two pairs of alkylating agents separated by 5 days of rest. The rest period was intended to provide time for recovery from the treatment-immediate adverse effects, thereby allowing further dose escalation. PATIENTS AND METHODS: The treatment consisted of thiotepa 225 to 300 mg/m2/d (days - 11 to -9), cisplatin 50 to 100 mg/m2/d (days - 11 and -3), and cyclophosphamide 60 mg/kg/d (days - 3 and -2). Dose escalation was performed in the initial 15 patients before reaching dose-limiting toxicities. When feasible, responding patients received posttransplant irradiation to sites of residual or prior bulky disease. Patients with bone marrow or CNS involvement, prior pelvic irradiation, or age greater than 55 years were excluded. RESULTS: Thirty-nine patients with measurable or assessable tumor were enrolled: 23 with visceral metastases, 11 with only soft tissue disease, and five with skeletal involvement. Twenty-five patients had received no chemotherapy for metastatic disease before transplantation. The dose-limiting toxicities of this therapy were renal and gastrointestinal. Six patients died from complications: four of a fungal infection and two of hemorrhage. A complete response was achieved in 14 patients (36%), three of whom are free of disease at 79+, 55+, and 40+ months after transplantation. Ten of 25 patients not treated with standard-dose chemotherapy for metastatic disease achieved a complete response (40%). The three patients in continuous remission were in the untreated relapse group. CONCLUSION: This single high-dose treatment achieved a relatively high complete response rate in patients with metastatic breast cancer and may have cured some of them. On the other hand, the split-course dose schedule as tested here did not permit significant dose-intensification.

Adult↗