The HERSCHEL detector consists of a set of scintillating counters, designed to increase the coverage of the LHCb experiment in the high-rapidity regions on either side of the main spectrometer. The ...new detector improves the capabilities of LHCb for studies of diffractive interactions, most notably Central Exclusive Production. In this paper the construction, installation, commissioning, and performance of HERSCHEL are presented.
Interaction cross sections and charged pion spectra in p+C interactions at 31 GeV/c were measured with the large-acceptance NA61/SHINE spectrometer at the CERN SPS. These data are required to improve ...predictions of the neutrino flux for the T2K long-baseline neutrino oscillation experiment in Japan. A set of data collected during the first NA61/SHINE run in 2007 with an isotropic graphite target with a thickness of 4% of a nuclear interaction length was used for the analysis. The measured p+C inelastic and production cross sections are 257.2 {+-} 1.9 {+-} 8.9 and 229.3 {+-} 1.9 {+-} 9.0 mb, respectively. Inclusive production cross sections for negatively and positively charged pions are presented as functions of laboratory momentum in ten intervals of the laboratory polar angle covering the range from 0 up to 420 mrad. The spectra are compared with predictions of several hadron production models.
We present a measurement of the momentum spectra of π±, K±, p±, Λ, ¯Λ, and K0S produced in interactions of negatively charged pions with carbon nuclei at beam momenta of 158 and 350 GeV/c. The total ...production cross sections are measured as well. The data were collected with the large-acceptance spectrometer of the fixed target experiment NA61/SHINE at the CERN SPS. The obtained double-differential p−pT spectra provide a unique reference dataset with unprecedented precision and large phase-space coverage to tune models used for the simulation of particle production in extensive air showers in which pions are the most numerous projectiles.
Time projection chambers for the T2K near detectors Abgrall, N.; Andrieu, B.; Baron, P. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2011, Letnik:
637, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The T2K experiment is designed to study neutrino oscillation properties by directing a high intensity neutrino beam produced at J-PARC in Tokai, Japan, towards the large Super-Kamiokande detector ...located 295
km away, in Kamioka, Japan. The experiment includes a sophisticated near detector complex, 280
m downstream of the neutrino production target in order to measure the properties of the neutrino beam and to better understand neutrino interactions at the energy scale below a few GeV. A key element of the near detectors is the ND280 tracker, consisting of two active scintillator–bar target systems surrounded by three large time projection chambers (TPCs) for charged particle tracking. The data collected with the tracker are used to study charged current neutrino interaction rates and kinematics prior to oscillation, in order to reduce uncertainties in the oscillation measurements by the far detector. The tracker is surrounded by the former UA1/NOMAD dipole magnet and the TPCs measure the charges, momenta, and particle types of charged particles passing through them. Novel features of the TPC design include its rectangular box layout constructed from composite panels, the use of bulk micromegas detectors for gas amplification, electronics readout based on a new ASIC, and a photoelectron calibration system. This paper describes the design and construction of the TPCs, the micromegas modules, the readout electronics, the gas handling system, and shows the performance of the TPCs as deduced from measurements with particle beams, cosmic rays, and the calibration system.
► First large scale time projection chambers with micropattern gas detectors. ► Incorporates new ASIC for electronic readout. ► Includes a pressure equalizing gas system and a photoelectron calibration system. ► Specifications achieved as deduced from neutrino, cosmic, and calibration tests. ► Will play an important role in T2K to measure neutrino oscillations.
The experiment of the NA61/SHINE Collaboration at the CERN SPS is performing a unique study of the phase diagram of strongly interacting matter by varying collision energy and nuclear mass number of ...colliding nuclei. In central Pb + Pb collisions, the experiment of the NA49 Collaboration found structures in the energy dependence of several observables in the energy range of the CERN SPS that had been predicted for the transition to a deconfined phase. New measurements of the NA61/SHINE Collaboration find intriguing similarities in $p + p$ interactions for which no deconfinement transition is expected at the energies of the SPS. Possible implications will be discussed.
The production of
K
S
0
mesons in inelastic
p+p
collisions at beam momentum 158
GeV
/
c
(
s
NN
=
17.3
GeV
) was measured with the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. ...Double-differential distributions were obtained in transverse momentum and rapidity. The mean multiplicity of
K
S
0
was determined to be
0.162
±
0.001
(
s
t
a
t
.
)
±
0.011
(
s
y
s
.
)
. The results on
K
S
0
production are compared with model predictions (
EPOS 1.99
, SMASH 2.0, PHSD and UrQMD 3.4 models) as well as with published world data.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The production cross section of 30.92 GeV/c protons on carbon is measured by the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron by means of beam attenuation in a copy (replica) of the ...90-cm-long target of the T2K neutrino oscillation experiment. The employed method for direct production cross-section estimation minimizes model corrections for elastic and quasielastic interactions. The obtained production cross section is σprod = 227.6 ± 0.8 (stat)+1.9−3.2 (sys) −0.8 (mod) mb. It is in agreement with previous NA61/SHINE results obtained with a thin carbon target, while providing improved precision with a total fractional uncertainty of less than 2%. This direct measurement will reduce the uncertainty of the T2K neutrino flux prediction.
Precise knowledge of hadron production rates in the generation of neutrino beams is necessary for accelerator-based neutrino experiments to achieve their physics goals. NA61/SHINE, a large-acceptance ...hadron spectrometer, has recorded hadron+nucleus interactions relevant to ongoing and future long-baseline neutrino experiments at Fermi National Accelerator Laboratory. This paper presents three analyses of interactions of 60 GeV/c π+ with thin, fixed carbon and beryllium targets. Integrated production and inelastic cross sections were measured for both of these reactions. In an analysis of strange, neutral hadron production, differential production multiplicities of KS0, Λ and Λ¯ were measured. Lastly, in an analysis of charged hadron production, differential production multiplicities of π+, π−, K+, K− and protons were measured. These measurements will enable long-baseline neutrino experiments to better constrain predictions of their neutrino flux in order to achieve better precision on their neutrino cross section and oscillation measurements.
Measurements of
K
∗
(
892
)
0
resonance production via its
K
+
π
-
decay mode in inelastic
p+p
collisions at beam momenta 40 and 80
GeV
/
c
(
s
NN
=
8.8
and 12.3
GeV
) are presented. The data were ...recorded by the NA61/SHINE hadron spectrometer at the CERN Super Proton Synchrotron. The
template
method was used to extract the
K
∗
(
892
)
0
signal. Transverse momentum and rapidity spectra were obtained. The mean multiplicities of
K
∗
(
892
)
0
mesons were found to be
(
35.1
±
1.3
(
stat
)
±
3.6
(
sys
)
)
·
10
-
3
at 40
GeV
/
c
and
(
58.3
±
1.9
(
stat
)
±
4.9
(
sys
)
)
·
10
-
3
at 80
GeV
/
c
. The NA61/SHINE results are compared with the
Epos1.99
and Hadron Resonance Gas models as well as with world data. The transverse mass spectra of
K
∗
(
892
)
0
mesons and other particles previously reported by NA61/SHINE were fitted within the Blast-Wave model. The transverse flow velocities are close to 0.1–0.2 of the speed of light and are significantly smaller than the ones determined in heavy nucleus-nucleus interactions at the same beam momenta.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
