Measurement of the Transverse Single-Spin Asymmetries for π 0 and Jet-like Events at Forward Rapidities at STAR in p+p Collisions at √s = 500 GeV Mriganka.

Slides:



Advertisements
Similar presentations
Longitudinal Spin at RHIC 29 th Winter Workshop on Nuclear Dynamics February 7, 2013 Cameron McKinney.
Advertisements

Carl Gagliardi – DIS2008 – Jets in pp at RHIC 1 Jet Production in Polarized pp Collisions at RHIC Carl A. Gagliardi Texas A&M University for the Collaboration.
Constraining the polarized gluon PDF in polarized pp collisions at RHIC Frank Ellinghaus University of Colorado (for the PHENIX and STAR Collaborations)
Jet and Jet Shapes in CMS
10/03/'06 SPIN2006, T. Horaguchi 1 Measurement of the direct photon production in polarized proton-proton collisions at  s= 200GeV with PHENIX CNS, University.
J. Seele - WWND 1 The STAR Longitudinal Spin Program Joe Seele (MIT) for the Collaboration WWND 2009.
Rapidity dependence of azimuthal correlations for pp and dAu Xuan Li (Shandong Uni. &BNL) For the STAR Collaboration WWND 2011 (Winter Park)
Carl Gagliardi – WWND – Trans Spin at RHIC 1 Transverse Spin Physics in pp Collisions at RHIC Carl A. Gagliardi Texas A&M University Outline Introduction.
STAR Len K. Eun For Collaboration Transverse Spin Physics at STAR 26 th Winter Workshop on Nuclear Dynamics Ochos Rios, Jamaica, January 2010.
Rapidity dependency of azimuthal correlations for pp and dAu Xuan Li (BNL&SDU) STAR Collaboration meeting (BNL, Nov 2010) 1Xuan Li.
Measurement of Forward Jet Production in polarized pp collisions at √s=500 GeV L. Nogach, IHEP (Protvino) for A N DY The 20th International Symposium on.
E.C. Aschenauer for the STAR Collaboration arXiv:
Status of Neutral Dijet Analysis on Data from 200GeV Proton Proton Collisions Using the STAR Detector at RHIC B. S. Page for the Collaboration STAR.
Constraining the Sivers Functions using Transverse Spin Asymmetries at STAR XII International Workshop on Deep Inelastic Scattering, Strbske Pleso, High.
Spin of the proton and its transverse spin structure at RHIC HERMES seminar at Tokyo Tech November 9, 2005 Yuji Goto (RIKEN)
Measurement of Transverse Single-Spin Asymmetries for Forward π 0 and Electromagnetic Jets in Correlation with Midrapidity Jet-like Events at STAR in p+p.
Jet Studies at CMS and ATLAS 1 Konstantinos Kousouris Fermilab Moriond QCD and High Energy Interactions Wednesday, 18 March 2009 (on behalf of the CMS.
Carl Gagliardi – STAR Transverse Spin Studies – DIS‘06 1 Transverse Spin Studies with STAR at RHIC Carl A. Gagliardi Texas A&M University for the Collaboration.
STAR Spin Related Future Upgrades STAR Spin Physics Program Current Capabilities Heavy Flavor Physics W Program Transverse Program Upgrades: Plans & Technologies.
Carl Gagliardi – STAR Spin: Recent Results, Future Directions 1 Spin Recent Results, Future Directions Carl A. Gagliardi Texas A&M University for the Collaboration.
PHENIX Local Polarimeter PSTP 2007 at BNL September 11, 2007 Yuji Goto (RIKEN/RBRC)
Columbia University Christine Aidala April 16, 2004 Single-Spin Transverse Asymmetry in Neutral Pion and Charged Hadron Production at DIS 2004, Slovakia.
Salvatore Fazio (Brookhaven National Lab) for the STAR Collaboration DIS 2014 – April 28 to May Transverse single-spin asymmetries in W ± and Z.
Oct 3 Spin2006 J.H. Lee (BNL) 1/29 SSA in BRAHMS J.H. Lee and F. Videbaek Physics Department Brookhaven National Laboratory for BRAHMS Collaboration Preliminary.
1 SSA in BRAHMS J.H. Lee (BNL) for BRAHMS Collaboration Preliminary Results on ,K,p Transverse Single Spin Asymmetries  at 200 GeV and 62 GeV  at high-x.
What can we learn from η production in proton-proton collisions? Joe Seele MIT and University of Colorado.
E.C. Aschenauer Why run top-energy p+p in run-16 2 Transverse momentum dependent parton distribution functions  initial state effects  important in.
1 Л.Ногач, ИФВЭ, Протвино the STAR Collaboration Односпиновая асимметрия в образовании π 0 - мезонов в области фрагментации поляризованного протонного.
Recent Spin and FMS Results at STAR Andrew Gordon Brookhaven National Laboratory Moriond-QCD March 14-21, 2009 STAR.
Measurements of Transverse Spin Effects with the Forward Pion Detector of STAR Larisa Nogach Institute of High Energy Physics, Protvino for the STAR collaboration.
1 34th International Conference on High Energy Physics (ICHEP 2008) ‏ The STAR Experiment Texas A&M University A. Hamed for the STAR collaboration Direct.
Searching for Polarized Glue at Brian Page – Indiana University For the STAR Collaboration June 17, 2014 STAR.
Single-Spin Asymmetries at CLAS  Transverse momentum of quarks and spin-azimuthal asymmetries  Target single-spin asymmetries  Beam single-spin asymmetries.
Transverse Single-Spin Asymmetries for Jet-like events at Forward Rapidities in p+p Collisions at √s = 500 GeV with the STAR Experiment APS April 5-8,
R&D Studies of a Lead-Scintillating Fiber Calorimeter as a STAR Forward Detector Prashanth Shanmuganathan (for FCal group at STAR)  Physics and R&D goals.
Renee Fatemi Massachusetts Institute of Technology February 28, 2005 Using Dijets to Measure the Gluon Sivers Functions at STAR.
STAR W.B. Christie, BNL RHIC Coordination meeting January 17, 2006 Outline Summary of STAR’s request for Run 6 Physics objectives Comments on Sam’s Draft.
Oct 6, 2008Amaresh Datta (UMass) 1 Double-Longitudinal Spin Asymmetry in Non-identified Charged Hadron Production at pp Collision at √s = 62.4 GeV at Amaresh.
Measurements with Polarized Hadrons T.-A. Shibata Tokyo Institute of Technology Aug 15, 2003 Lepton-Photon 2003.
Jet Physics at CDF Sally Seidel University of New Mexico APS’99 24 March 1999.
James L. Drachenberg For the STAR Collaboration October 1, 2013 OUTLINE Introduction Event Selection Analysis Description Systematic Uncertainties Preliminary.
Jan Balewski: Di-jet Sivers in 200 GeV 1 Outline Motivation Principle of measurement, trigger Model of Sivers asymmetry Measured SSA & DSA Comparison.
Transverse Single-Spin Asymmetries Understanding the Proton: One of the fundamental building blocks of ordinary matter! Spin decomposition of proton still.
MPC-EX hardware design and capability The MPC-EX detector system is an extension of the existing Muon Piston Calorimeters (MPCs) of the PHENIX experiment.
Longitudinal Spin Asymmetry and Cross Section of Inclusive  0 Production in Polarized p+p Collisions at 200 GeV Outline  Introduction  Experimental.
N. Poljak, FPD++ N. Poljak, U. of Zagreb.
Measurement of inclusive jet and dijet production in pp collisions at √s = 7 TeV using the ATLAS detector Seminar talk by Eduardo Garcia-Valdecasas Tenreiro.
Measurement of the Double Longitudinal Spin Asymmetry in Inclusive Jet Production in Polarized p+p Collisions at 200 GeV Outline Introduction RHIC.
Jet Studies at CDF Anwar Ahmad Bhatti The Rockefeller University CDF Collaboration DIS03 St. Petersburg Russia April 24,2003 Inclusive Jet Cross Section.
October 2011 David Toback, Texas A&M University Research Topics Seminar1 David Toback Texas A&M University For the CDF Collaboration CIPANP, June 2012.
Oct. 12, 2007 Imran Younus k T Asymmetry in Longitudinally Polarized p +p Collisions at PHENIX.
UMass Amherst Christine Aidala June 15, 2006 Accessing Transversity via Collins and Interference Fragmentation at RHIC QCDN-06, Rome.
October 22, 2004 Single Spin Asymmetries at RHIC 1 F.Videbaek Physics Department, Brookhaven National.
The STAR Experiment Texas A&M University A. M. Hamed for the STAR collaboration 1 Quark Matter 2009 Knoxville, TN.
 -jet measurements Table of Contents:  Motivation  Preliminary QA of  -trigger Data  Shower Shape Analysis  Experimental Challenges  Summary  
Inclusive cross section and single transverse-spin asymmetry of very forward neutron production at PHENIX Spin2012 in Dubna September 17 th, 2012 Yuji.
Gluon polarization and jet production at STAR Pibero Djawotho for the STAR Collaboration Texas A&M 4 June 2013.
1 Small x and Forward Physics in pp/pA at RHIC STAR Forward Physics FMS Steve Heppelmann Steve Heppelmann Penn State University STAR.
STAR Summary for 2012 pp running May 11, 2012 Bill Christie, BNL Outline Summary of 200 GeV pp run Summary of 510 GeV pp run STAR’s running efficiency.
RHIC Results on Transverse Spin Steve Heppelmann Penn State University 2nd Workshop on the QCD Structure of the Nucleon June 12-16, 2006 Villa Mondragone.
Theoretical Interpretation of Forward Neutron AN
Can We Learn Quark Orbital Motion from SSAs?
Larisa Nogach Institute of High Energy Physics, Protvino
Unique Description for SSAs in DIS and Hadronic Collisions
Accessing Transversity via Collins and Interference Fragmentation at RHIC Christine Aidala UMass Amherst QCDN-06, Rome June 15, 2006.
PHENIX Transverse-Spin Physics
Katarzyna Kowalik (LBNL) For the STAR Collaboration
Kazuya Aoki For the PHENIX Collaborations. Kyoto Univ. / RIKEN
Unique Description for Single Transverse Spin Asymmetries
Recent results from high-energy longitudinal polarized proton-proton collisions at 200GeV at RHIC Tai Sakuma MIT
Presentation transcript:

Measurement of the Transverse Single-Spin Asymmetries for π 0 and Jet-like Events at Forward Rapidities at STAR in p+p Collisions at √s = 500 GeV Mriganka Mouli Mondal (for STAR experiment) Texas A&M University DIS 2014, Warsaw, Apr. 28-May 2, 20141

Outline  Transverse Single Spin Asymmetries (TSSA)  Forward Meson Spectrometer in the STAR experiment  EM-Jets in forward and central rapidity  A N measurements from RHIC Run 11 at √s = 500 GeV DIS 2014, Warsaw, Apr. 28-May 2, 20142

TSSA - 2 theoretical frameworks Spin-dependent transverse momentum dependent (TMD) function S T.(Pxk T ) Brodsky, Hwang, Schmidt, 02 Collins, 02, Ji, Belitsky, Yuan, 02 Twist-3 quark-gluon correlations Efremov & Teryaev: 1982 & 1984 Qiu & Sterman: 1991 & 1999 Sivers fct. Q  QCD Q T /P T << Q T /P T Transverse momentum dependent Q>>Q T >=  QCD Q>>p T Collinear/ twist-3 Q,Q T >>  QCD p T ~Q Efremov, Teryaev; Qiu, Sterman Need 2 scales Q 2 and p t Remember pp: most observables one scale Exception: DY, W/Z-production Need only 1 scale Q 2 or p t But should be of reasonable size should be applicable to most pp observables A N (  0 /  /jet) Intermediate Q T Q>>Q T /p T >>  QCD DIS 2014, Warsaw, Apr. 28-May 2, pp-pA-LoI f2f, February 2014 E.C. Aschenauer ANAN

π 0 A N Measurements at Forward Rapidity  Rising A N with X F  A N nearly independent of √s  No evidence of fall in A N with increasing P T Transverse Single Spin Asymmetry Inclusive π 0 production x F = 2p Z /√s DIS 2014, Warsaw, Apr. 28-May 2, 20144

500 GeV Isolated π 0 results DIS 2014, Warsaw, Apr. 28-May 2, are  A N is higher with increasing isolation radius  A N in increasing with x F DIS-2013 (Steven Heppelmann)

200 GeV Isolated π 0 results DIS 2014, Warsaw, Apr. 28-May 2, DIS-2013 (Steven Heppelmann)  Events opposite “side photons” or “no” photons have similar A N  Same side photons lead to much reduced A N

RHIC : the world’s first and only polarized proton collider Beams: √s GeV pp DIS 2014, Warsaw, Apr. 28-May 2, For 2011 : Average Blue Beam Polarization = 51.6% (Transverse) Luminosity =22 pb-1

Forward ECAL in STAR Forward Meson Spectrometer (FMS) : -- Pb glass EM calorimeter covering 2.6<η< Detect 0,η, direct photons and jet-like events in the kinematic region where transverse spin asymmetries are known to be large. FMS Pb Glass EM Calorimeter pseudo-rapidity 2.6<  <4.0 Small cells: Outer cells: 3.81x3.81 cm 5.81 x 5.81 cm DIS 2014, Warsaw, Apr. 28-May 2, 20148

BEMC EEMC FMS FPD TPC BBC ZDC VPD DIS 2014, Warsaw, Apr. 28-May 2, FMS photon reconstruction : towers  clusters  photon shower shape fitting BEMC+EEMC towers : to find central electromagnetic jets FMS photons : to find forward electromagnetic jets STAR detector cross view

RHIC Run 11 (2011) √s=500 GeV Forward Electromagnetic Jets (EM-Jets) Jet algorithm : anti-k T R-parameter : 0.7 p T EM-Jet > 2.0 GeV/c Leading EM-Jets : defined as EM-Jets with highest energy. 2.8<η EM-Jet < GeV < Energy EM-Jet < 100 GeV (0.16 < x F < 0.4) # Jets Structure in EM-Jet p T : -- Acceptance non uniformity in small and large tower boundary inside FMS -- Different trigger threshold influence different p T region DIS 2014, Warsaw, Apr. 28-May 2,

Forward EM-Jet characteristics  2-photon jets are mostly π 0  Events with more than 2 photons show jet-like energy flow No. of photons in leading EM-Jets γγ invariant mass 2-photon EM-jets dE/d(ΔR) distribution of EM-Jets EM-Jet Energy GeV Z γγ < 0.8, no. photons = 2 EM-Jet Energy GeV # Jets dE/d(ΔR) (arbitrary scale) DIS 2014, Warsaw, Apr. 28-May 2,

A N from fits EM-Jet Energy = GeV For 2-photon isolated π 0 For each slice of data averaged over ~18 fills. Fits are well in control. DIS 2014, Warsaw, Apr. 28-May 2,  A N is calculated from p0 + P×A N cos(ϕ) fits over each fill on p0 = relative luminosity A N = asymmetry P = polarization --- A N ’s are corrected for polarization values from RHIC-fills --- A N and χ 2 /NDF are calculated over entire fills

A N vs. EM-Jet Energy π 0 -Jets – 2γ-EM-Jets with m γγ <0.3 Z γγ <0.8 EM-Jets – with no. photons >2  Isolated π 0 ’s have large asymmetries consistent with previous observation (CIPANP-2012 Steven Heppelmann)  Asymmetries for jettier events are much smaller DIS 2014, Warsaw, Apr. 28-May 2,

A N vs. EM-Jet Energy  Isolated π 0 ’s have large asymmetries consistent with previous observation (CIPANP-2012 Steven Heppelmann)  Asymmetries for jettier events are much smaller π 0 -Jets – 2γ-EM-Jets with m γγ <0.3 Z γγ <0.8 2γ-EM-Jets (η + continuum) - with m γγ > 0.3 EM-Jets – with no. photons >2 DIS 2014, Warsaw, Apr. 28-May 2,

A N for different # photons in EM-Jets  1-photon events, which include a large π 0 contribution in this analysis, are similar to 2- photon events  Three-photon jet-like events have a clear non- zero asymmetry, but substantially smaller than that for isolated π 0 ’s  A N decreases as the event complexity increases (i.e., the "jettiness”  A N for #photons >5 is similar to that for #photons = 5 DIS 2014, Warsaw, Apr. 28-May 2, Jettier events

A N with midrapidity activities DIS 2014, Warsaw, Apr. 28-May 2, 2014 η = 1.09,2.0 η = BEMC EEMC FMS η = -1.0,1.0 central EMJets forward EMJets Case-I : having no central jet Case-II : having a central jet Jet algorithm : anti-k T, R = 0.7 p T EM-Jet > 2.0 GeV/c, -1.0<η EM-Jet <2.0 Inputs for central EMJets : towers from BEMC and EEMC Leading central EM-Jets : Jet with highest p T Midrapidity EM Jets 16

Characteristics of Coincident Central EM-Jets (case-II) Energy flow within central EMJets energy sharing (asymmetric scatterings) Forward-central correlations For Central EMJets DIS 2014, Warsaw, Apr. 28-May 2, p T distribution p T balance (di-jet like) central/forward

Δφ correlation between forward and central EMJets DIS 2014, Warsaw, Apr. 28-May 2, 2014  Correlation is stronger for more N_photon Jets  For higher EMJets energy, correlation grows stronger 18 Number of photons for forward EMJets : 1,2 3 and more

A N for with and without a central EM-Jet DIS 2014, Warsaw, Apr. 28-May 2,  An EM-jet in the central rapidity region reduces the asymmetries for the forward isolated π

A N for the central jet : near and away in ϕ to the forward jet DIS 2014, Warsaw, Apr. 28-May 2, Near and away side Correlated central EM-Jet Uncorrelated central EM-Jet  Uncorrelated central EM-Jet is separated out

A N for correlated central jets and no central jet cases DIS 2014, Warsaw, Apr. 28-May 2, ≈√  Asymmetries for the forward isolated π 0 are low when there is a correlated away-side jet.

Conclusion  EM-jets are reconstructed from photons detected in the FMS at STAR.  Jets with isolated π 0 have large asymmetry.  Three-photon jet-like events have a clear non-zero asymmetry, but substantially smaller than that for isolated π 0 ’s.  A N decreases as the event complexity increases(i.e., the "jettiness”)  Isolated π 0 asymmetries are smaller when there is a correlated EM- jet at mid-rapidity.  Both of these dependences raise serious question how much of the large forward π 0 A N comes from 2  2 parton scattering. DIS 2014, Warsaw, Apr. 28-May 2,

Backup.. Systematics arising from intermixing of event classes DIS 2014, Warsaw, Apr. 28-May 2, PRD (R) (2012)

No EM-jet within GeV/c) DIS 2014, Warsaw, Apr. 28-May 2,

With a EM-jet with GeV/c) DIS 2014, Warsaw, Apr. 28-May 2,