Search for New Phenomena in Dijet Angular Distributions in Proton-Proton Collisions at $\sqrt{s} = 8$ TeV Measured with the ATLAS Detector

A search for new phenomena in LHC proton-proton collisions at a center-of-mass energy of s=8 TeV was performed with the ATLAS detector using an integrated luminosity of 17.3 fb−1. The angular distributions are studied in events with at least two jets; the highest dijet mass observed is 5.5 TeV. All angular distributions are consistent with the predictions of the standard model. In a benchmark model of quark contact interactions, a compositeness scale below 8.1 TeV in a destructive interference scenario and 12.0 TeV in a constructive interference scenario is excluded at 95% C.L.; median expected limits are 8.9 TeV for the destructive interference scenario and 14.1 TeV for the constructive interference scenario.

Note:

4 pages plus author list + cover pages (17 pages total), 1 figures, submitted to PRL, All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2014-15/

13.85.Rm
12.60.Rc
p p: colliding beams
jet: pair production
dijet: angular distribution
dijet: mass
p p: scattering
new interaction: search for
interference
constructive

References(45)

Figures(1)

[1]

Black Holes and Quantum Gravity at the LHC

- JHEP 05 (2008) 003
•
e-Print:
- 0708.3017
•
DOI:
- 10.1088/1126-6708/2008/05/003

[2]

Inelastic black hole production and large extra dimensions

Luis A. Anchordoqui
(
- Northeastern U.
)
,
Jonathan L. Feng
(
- UC, Irvine
)
,
Haim Goldberg
(
- Northeastern U.
)
,
Alfred D. Shapere
(
- Kentucky U.
)

- Phys.Lett.B 594 (2004) 363-367
•
e-Print:
- hep-ph/0311365
•
DOI:
- 10.1016/j.physletb.2004.05.051

[3]

Excited Quark Production at Hadron Colliders

U. Baur
(
- Fermilab
)
,
I. Hinchliffe
(
- LBL, Berkeley
)
,
D. Zeppenfeld
(
- Wisconsin U., Madison
)

- Int.J.Mod.Phys.A 2 (1987) 1285,
- Madison Supercoll.Wkshp.1987:0395
•
DOI:
- 10.1142/S0217751X87000661

[4]

Excited Quark and Lepton Production at Hadron Colliders

U. Baur
(
- Wisconsin U., Madison
)
,
M. Spira
(
- Aachen, Tech. Hochsch.
)
,
P.M. Zerwas
(
- Aachen, Tech. Hochsch.
)

- Phys.Rev.D 42 (1990) 815-824
•
DOI:
- 10.1103/PhysRevD.42.815

[5]

Super Collider Physics

- Rev.Mod.Phys. 56 (1984) 579-707,
- Rev.Mod.Phys. 58 (1986) 1065-1073 (addendum)
•
DOI:
- 10.1103/RevModPhys.56.579

[6]

Possible bounds on compositeness from inclusive one jet production in large hadron colliders

P. Chiappetta
(
- Marseille, CPT
)
,
M. Perrottet
(
- Marseille, CPT
)

- Phys.Lett.B 253 (1991) 489-493
•
DOI:
- 10.1016/0370-2693(91)91757-M

[7]

Angular Distributions and Structure Functions from Two Jet Events at the CERN SPS $p \bar{p}$ Collider

UA1

Collaboration

•

G. Arnison
(
- Rutherford
)

et al.

- Phys.Lett.B 136 (1984) 294-300
•
DOI:
- 10.1016/0370-2693(84)91164-X

[8]

Measurement of Jet Production Properties at the CERN anti-p p Collider

Collaborations

•

P. Bagnaia
(
- CERN
)

et al.

- Phys.Lett.B 144 (1984) 283-290
•
DOI:
- 10.1016/0370-2693(84)91822-7

[9]

Search for new particles decaying into dijets in proton-antiproton collisions at s**(1/2) = 1.96-TeV

CDF

Collaboration

•

T. Aaltonen
(
- Helsinki Inst. of Phys.
)

et al.

- Phys.Rev.D 79 (2009) 112002
•
e-Print:
- 0812.4036
•
DOI:
- 10.1103/PhysRevD.79.112002

[10]

Measurement of dijet angular distributions at s**(1/2) = 1.96-TeV and searches for quark compositeness and extra spatial dimensions

D0

Collaboration

•

V.M. Abazov
(
- Dubna, JINR
)

et al.

- Phys.Rev.Lett. 103 (2009) 191803
•
e-Print:
- 0906.4819
•
DOI:
- 10.1103/PhysRevLett.103.191803

[11]

Search for Quark Contact Interactions in Dijet Angular Distributions in $pp$ Collisions at $\sqrt{s}=7$ TeV Measured with the ATLAS Detector

ATLAS

Collaboration

•

G. Aad
(
- Freiburg U.
)

et al.

- Phys.Lett.B 694 (2011) 327-345
•
e-Print:
- 1009.5069
•
DOI:
- 10.1016/j.physletb.2010.10.021

[12]

Search for Dijet Resonances in 7 TeV pp Collisions at CMS

CMS

Collaboration

•

Vardan Khachatryan
(
- Yerevan Phys. Inst.
)

et al.

- Phys.Rev.Lett. 105 (2010) 211801
•
e-Print:
- 1010.0203
•
DOI:
- 10.1103/PhysRevLett.105.211801

[13]

Search for Quark Compositeness with the Dijet Centrality Ratio in $pp$ Collisions at $\sqrt{s}=7$ TeV

CMS

Collaboration

•

Vardan Khachatryan
(
- Yerevan Phys. Inst.
)

et al.

- Phys.Rev.Lett. 105 (2010) 262001
•
e-Print:
- 1010.4439
•
DOI:
- 10.1103/PhysRevLett.105.262001

[14]

Measurement of Dijet Angular Distributions and Search for Quark Compositeness in pp Collisions at $sqrt{s} = 7$ TeV

CMS

Collaboration

•

Vardan Khachatryan
(
- Yerevan Phys. Inst.
)

et al.

- Phys.Rev.Lett. 106 (2011) 201804
•
e-Print:
- 1102.2020
•
DOI:
- 10.1103/PhysRevLett.106.201804

[15]

Search for New Physics in Dijet Mass and Angular Distributions in pp Collisions at $\sqrt{s} = 7$ TeV Measured with the ATLAS Detector

ATLAS

Collaboration

•

Georges Aad
(
- Freiburg U.
)

et al.

- New J.Phys. 13 (2011) 053044
•
e-Print:
- 1103.3864
•
DOI:
- 10.1088/1367-2630/13/5/053044

[16]

ATLAS search for new phenomena in dijet mass and angular distributions using $pp$ collisions at $\sqrt{s}=7$ TeV

ATLAS

Collaboration

•

Georges Aad
(
- Freiburg U.
)

et al.

- JHEP 01 (2013) 029
•
e-Print:
- 1210.1718
•
DOI:
- 10.1007/JHEP01(2013)029

[17]

Search for quark contact interactions and extra spatial dimensions using dijet angular distributions in proton–proton collisions at $\sqrt s =$ 8 TeV

CMS

Collaboration

•

Vardan Khachatryan
(
- Yerevan Phys. Inst.
)

et al.

- Phys.Lett.B 746 (2015) 79-99
•
e-Print:
- 1411.2646
•
DOI:
- 10.1016/j.physletb.2015.04.042

[18]

The ATLAS Experiment at the CERN Large Hadron Collider

ATLAS

Collaboration

•

G. Aad
(
- Marseille, CPPM
)

et al.

- JINST 3 (2008) S08003
•
DOI:
- 10.1088/1748-0221/3/08/S08003

[19]

uses a right-handed coordinate system with its origin at the nominal interaction point (IP) in the center of the detector and the z-axis along the beam pipe. The x-axis points from the IP to the center of the LHC ring, and the y-axis points upward. Cylindrical coordinates (r, φ) are used in the transverse plane, φ being the azimuthal angle around the beam pipe. The pseudorapidity is defined in terms of the polar angle θ as η = - ln [tan(θ/2)]. The transverse energy and transverse momentum are defined by ET = E sin θ and pT = |p| sin θ, respectively