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Answer: Yes, we know that scaling is strongly violated! 6
Cold Nuclear Matter Effects: the “Initial State”
7
Cronin Effect
In p+A collisions: Parameterization done by Cronin et al.
F.Karsch, Lect.Notes.Phys 583, 209 (2002)
Understanding the transition as a change of the number of degrees of freedom: Below Tc : dilute gas of 3 states of pions Above Tc : for 2 flavors we have
pT
11
Hot and Dense Nuclear Matter Effects: the Final State
12
A new state of matter
Hypothesis: hadronic matter undergoes a phase transition as temperature reaches T~170 MeV Supported by the decrease of the strong coupling constant as a function of energy. Energy density increases over an order of magnitude in a narrow range of temperatures 10-20 MeV Lattice QCD provides the most quantitave theoretical support to this day.
Identified Particle Production in p+p and d+Au Collisions at RHIC Energies
Felix Matathias Doctoral Defense Adviser: Tom Hemmick
State University of New York at Stony Brook December 8, 2014, New York
The goal of Comparative Literature is:
“…to compare literature in different languages and literature with relation to some other field…” “…compare properties of particle production in different nuclear environments and as a function of particle flavor…”
Alpha factors are:
pt-dependent species-dependent
Cronin effect Enhancement at high-pt Shadowing at low-pt Mechanism: Initial parton multiple scattering
Saturation moment:
The scale at which nonlinear effects start to be important in the hadron wavefunction.
2 Q0 ~ 2 GeV
@130 GeV ( RHIC )
2 Qs ( ) ~
2 Nc
as N c xG( x, Q 2 ) 1
Definition of point-like scaling:
hard . AB
RAB A B
hard NN
,
RAB 1
Do we already know anything about the scaling properties of hard scattering ?
R
2
as A1 / 3
For Q>>Q_saturation() non-linear effects are negligible and linear evolution effects apply (BFKL, DGLAP)
10
The net effect of parton saturation is particle suppression.
8
Antreasyan et.al.Phys.Rev.D19(3)1979
Parton Saturation
Linear evolution (DGLAP) leads to violation of unitarity. At some point, the parton density acquires a negative term:
2
Comparative Nuclear Physics II
In this work we will be comparing particle production at
Center of Mass Energy: √s=200GeV Different nuclear environments:
9
The onset of parton saturation
“Packing” factor
k (Q 2 ) n( x, Q 2 ) ~
as N c Q
2
1
2 Nc 1
xG( x, Q 2 )
R2
Onset of saturation: k~1
Solution in the x-Q plane.
(Phys.Rev.D11,3105,1975)
2 d / d p(T B pA a i pt ) R p ) ) I ( pt,1) A T I( ( pt , A 2 i i Ad / d pT pB
Straub et.al Phys.Rev.Lett.68(4)1992
Questions that this thesis will answer: What is the size of the Cronin effect at RHIC energies ? What is the species-dependence of the Cronin effect at RHIC energies ? What is the energy dependence of the Cronin effect at RHIC energies compared to Fermilab observations?
1
Comparative Nuclear Physics
Yesterday it occurred to me that the core concept of my thesis is not so different than what my wife does for a living. My wife is a Ph.D. student in Comparative Literature at Stony Brook. I gave her a call last night and asked her for a short definition of her field. She repeatedly asked my why I needed it and seemed confused (and concerned).
p+p collisions d+Au collisions Au+Au collisions
Particle species: pions, Kaons, (anti)protons
The physical observables will be
Differential yield per inelastic collision in the d+Au and Au+Au case Invariant differential cross sections in the p+p case
Phys. Let. B561, 93 (2003)
d
Non-saturated deuteron wave function
“Cronin”
pT
A
Saturated nuclear wave function
“Suppressed”
This thesis answers the question: enhancement or suppresion for identified particles ?
5
Does nuclear size matter ? (Yes, but in mysterious ways)
Comparing particle production in different nuclear environments wouldn’t be that interesting if everything scaled according to the size of the colliding system
Au+Au: 0.1 p+p : 10
The machine
Top energies (each beam):
100 GeV/nucleon Au+Au. 100 GeV/nucleon d+Au 100 GeV polarized p+p
ห้องสมุดไป่ตู้
4
The detector
Maximal Set of Observables Photons, Electrons, Muons, ID-hadrons Highly Selective Triggering High Rate Capability. Rare Processes. But rare processes always come late in the game for collider experiments due to limited luminosity. But I wanted a thesis at some point. Therefore I utilize the copious production of hadrons, through the strong nuclear force, albeit with a relatively small detector.
3
Relativistic Heavy Ion Collider Brookhaven National Lab 2 counter-circulating rings 3.834 km circumference Superconducting magnets(3.5T) 192 dipoles per ring 246 quadrupoles per ring Time between collisions: 0.213 microseconds Crossing angle: 0 Bunch length: 20 cm Bunches per ring: 56 Luminosity lifetime: 3-10 hours Particles per bunch (units 1010):
In that vein, I define the goal of Comparative Nuclear Physics to be:
Obviously this is a narrow definition that I made up to define the goal of my thesis. It could easily though be extended to a more general definition. The main point though is that my wife may become interested in what I do.
Cold Nuclear Matter Effects: the “Initial State”
7
Cronin Effect
In p+A collisions: Parameterization done by Cronin et al.
F.Karsch, Lect.Notes.Phys 583, 209 (2002)
Understanding the transition as a change of the number of degrees of freedom: Below Tc : dilute gas of 3 states of pions Above Tc : for 2 flavors we have
pT
11
Hot and Dense Nuclear Matter Effects: the Final State
12
A new state of matter
Hypothesis: hadronic matter undergoes a phase transition as temperature reaches T~170 MeV Supported by the decrease of the strong coupling constant as a function of energy. Energy density increases over an order of magnitude in a narrow range of temperatures 10-20 MeV Lattice QCD provides the most quantitave theoretical support to this day.
Identified Particle Production in p+p and d+Au Collisions at RHIC Energies
Felix Matathias Doctoral Defense Adviser: Tom Hemmick
State University of New York at Stony Brook December 8, 2014, New York
The goal of Comparative Literature is:
“…to compare literature in different languages and literature with relation to some other field…” “…compare properties of particle production in different nuclear environments and as a function of particle flavor…”
Alpha factors are:
pt-dependent species-dependent
Cronin effect Enhancement at high-pt Shadowing at low-pt Mechanism: Initial parton multiple scattering
Saturation moment:
The scale at which nonlinear effects start to be important in the hadron wavefunction.
2 Q0 ~ 2 GeV
@130 GeV ( RHIC )
2 Qs ( ) ~
2 Nc
as N c xG( x, Q 2 ) 1
Definition of point-like scaling:
hard . AB
RAB A B
hard NN
,
RAB 1
Do we already know anything about the scaling properties of hard scattering ?
R
2
as A1 / 3
For Q>>Q_saturation() non-linear effects are negligible and linear evolution effects apply (BFKL, DGLAP)
10
The net effect of parton saturation is particle suppression.
8
Antreasyan et.al.Phys.Rev.D19(3)1979
Parton Saturation
Linear evolution (DGLAP) leads to violation of unitarity. At some point, the parton density acquires a negative term:
2
Comparative Nuclear Physics II
In this work we will be comparing particle production at
Center of Mass Energy: √s=200GeV Different nuclear environments:
9
The onset of parton saturation
“Packing” factor
k (Q 2 ) n( x, Q 2 ) ~
as N c Q
2
1
2 Nc 1
xG( x, Q 2 )
R2
Onset of saturation: k~1
Solution in the x-Q plane.
(Phys.Rev.D11,3105,1975)
2 d / d p(T B pA a i pt ) R p ) ) I ( pt,1) A T I( ( pt , A 2 i i Ad / d pT pB
Straub et.al Phys.Rev.Lett.68(4)1992
Questions that this thesis will answer: What is the size of the Cronin effect at RHIC energies ? What is the species-dependence of the Cronin effect at RHIC energies ? What is the energy dependence of the Cronin effect at RHIC energies compared to Fermilab observations?
1
Comparative Nuclear Physics
Yesterday it occurred to me that the core concept of my thesis is not so different than what my wife does for a living. My wife is a Ph.D. student in Comparative Literature at Stony Brook. I gave her a call last night and asked her for a short definition of her field. She repeatedly asked my why I needed it and seemed confused (and concerned).
p+p collisions d+Au collisions Au+Au collisions
Particle species: pions, Kaons, (anti)protons
The physical observables will be
Differential yield per inelastic collision in the d+Au and Au+Au case Invariant differential cross sections in the p+p case
Phys. Let. B561, 93 (2003)
d
Non-saturated deuteron wave function
“Cronin”
pT
A
Saturated nuclear wave function
“Suppressed”
This thesis answers the question: enhancement or suppresion for identified particles ?
5
Does nuclear size matter ? (Yes, but in mysterious ways)
Comparing particle production in different nuclear environments wouldn’t be that interesting if everything scaled according to the size of the colliding system
Au+Au: 0.1 p+p : 10
The machine
Top energies (each beam):
100 GeV/nucleon Au+Au. 100 GeV/nucleon d+Au 100 GeV polarized p+p
ห้องสมุดไป่ตู้
4
The detector
Maximal Set of Observables Photons, Electrons, Muons, ID-hadrons Highly Selective Triggering High Rate Capability. Rare Processes. But rare processes always come late in the game for collider experiments due to limited luminosity. But I wanted a thesis at some point. Therefore I utilize the copious production of hadrons, through the strong nuclear force, albeit with a relatively small detector.
3
Relativistic Heavy Ion Collider Brookhaven National Lab 2 counter-circulating rings 3.834 km circumference Superconducting magnets(3.5T) 192 dipoles per ring 246 quadrupoles per ring Time between collisions: 0.213 microseconds Crossing angle: 0 Bunch length: 20 cm Bunches per ring: 56 Luminosity lifetime: 3-10 hours Particles per bunch (units 1010):
In that vein, I define the goal of Comparative Nuclear Physics to be:
Obviously this is a narrow definition that I made up to define the goal of my thesis. It could easily though be extended to a more general definition. The main point though is that my wife may become interested in what I do.