The Ricochet experiment aims to measure the coherent elastic neutrino-nucleus scattering process from antineutrinos emitted by a research nuclear reactor operated by the Institut Laue-Langevin (Grenoble, France). This article presents a description of the Ricochet experimental installation and the detector performance achieved during its commissioning with a mini-CryoCube module consisting of three 42-g germanium cryogenic calorimeters. The baseline resolutions and background levels are reported both during reactor-on and reactor-off periods and as noise mitigation techniques were improved. A baseline resolution of 40 eV electron equivalent was achieved for the ionization channel after setup improvements, and the phonon channel resolutions ranged from 50 to 80 eV of total phonon energy. In the energy region from 2 to 7 keV, a nuclear recoil rate of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>14</mn><mo stretchy="false">(</mo><mn>3</mn><mo stretchy="false">)</mo><mtext> </mtext><mtext> </mtext><mi>events</mi><mo>/</mo><mo stretchy="false">(</mo><mi>kg</mi><mtext> </mtext><mi>day</mi><mtext> </mtext><mtext> </mtext><mi>keV</mi><mo stretchy="false">)</mo></mrow></math> is measured during the reactor-off period selecting events in coincidence with muon veto signals. This rate is in agreement with the cosmogenic neutron rate calculated from GEANT4 simulations. After the rejection of events in coincidence with signals in the muon veto detectors, a combined 90% confidence level limit on the nuclear recoil background of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mo form="prefix">&lt;</mo><mn>9</mn><mtext> </mtext><mtext> </mtext><mi>events</mi><mo>/</mo><mo stretchy="false">(</mo><mi>kg</mi><mtext> </mtext><mi>day</mi><mtext> </mtext><mi>keV</mi><mo stretchy="false">)</mo></mrow></math> is obtained in that energy region during the reactor-on period, which is compatible with our GEANT4 model calculation corresponding to a total rate of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>5</mn><mtext> </mtext><mtext> </mtext><mi>events</mi><mo>/</mo><mo stretchy="false">(</mo><mi>kg</mi><mtext> </mtext><mi>day</mi><mtext> </mtext><mi>keV</mi><mo stretchy="false">)</mo></mrow></math>. The sensitivity of this analysis was however found to be limited by a surface event contamination which is currently being addressed by the Ricochet Collaboration with upgraded detectors.

France

A. Armatol

C. Augier

L. Bailly-Salins

G. Baulieu

L. Bergé

J. Billard

J. Blé

G. Bres

J-.L. Bret

A. Broniatowski

M. Calvo

A. Cavanna

A. Cazes

United States

E. Celi

D. Chaize

M. Chala

M. Chapellier

L. Chaplinsky

G. Chemin

R. Chen

J. Colas

L. Couraud

Canada

E. Cudmore

M. De Jesus

N. Dombrowski

L. Dumoulin

A. Durnez

O. Exshaw

S. Ferriol

E. Figueroa-Feliciano

J.A. Formaggio

S. Fuard

J. Gascon

A. Giuliani

C. Goy

C. Guerin

E. Guy

L. Haegel

S.A. Hertel

C. Hoarau

Z. Hong

J.C. Ianigro

Y. Jin

A. Juillard

JINR

T. Khussainov

A. Kubik

J. Lamblin

H. Lattaud

T. Le Bellec

L. Leroy

M. Li

A. Lubashevskiy

S. Marnieros

N. Martini

J. Minet

A. Monfardini

F. Mounier

V. Novati

E. Olivieri

P.K. Patel

E. Perbet

H.D. Pinckney

D.V. Poda

D. Ponomarev

W. Van De Pontseele

J.S. Real

F.C. Reyes

A. Rodriguez

M. Rousseau

S. Rozov

I. Rozova

B. Ryan

D. Sabhari

S. Scorza

R. Serra

Ye. Shevchik

T. Soldner

A. Stutz

Ch. Ulysse

L. Vagneron

S. Vasilyev

F. Vezzu

P. Vittaz

E. Yakushev

J. Yang

D. Zinatulina

Characterization of mini-CryoCube detectors from the RICOCHET experiment commissioning at the Institut Laue-Langevin

The (Calibrated nuclear Recoils for Accurate Bolometry) project aims to precisely characterize the response of cryogenic detectors to sub-keV nuclear recoils of direct interest for coherent neutrino-nucleus scattering and dark matter search experiments. The method relies on the radiative capture of thermal neutrons in the target detector, resulting in a nuclear recoil with a well-defined energy. We present a new experimental setup installed at the TRIGA Mark-II reactor at Atominstitut (Vienna), providing a low intensity beam of thermal neutrons sent to the target cryogenic detector mounted inside a wet dilution refrigerator Kelvinox 100. After the presentation of all components of the setup we report the analysis of first commissioning data with CaWO $$_{4}$$ detectors of the experiment. They show stable operation of the cryostat and detectors on a week-scale. Due to an energy resolution currently limited to 20 eV we use neutron beam induced events at high energy, in the 10 to 100 keV range, to demonstrate the excellent agreement between the data and simulation and the accurate understanding of external background. Thanks to these data we also propose an updated decay scheme of the low-lying excited states of $$^{187}$$ W. Finally, we present the first evidence of neutron-capture induced coincidences between BaF $$_2$$ $$\gamma $$ -detectors installed around the dewar and the inner cryogenic detector. These promising results pave the way for an extensive physics program with various detector materials, like CaWO $$_{4}$$ , Al $$_{2}$$ O $$_{3}$$ , Ge and Si.

Austria

H. Abele

Germany

P. Ajello

B. Arnold

E. Bossio

J. Burkhart

Italy

F. Cappella

N. Casali

R. Cerulli

J.P. Crocombette

G. Castello

M. Gallo Roccagiovine

S. Dorer

C. Doutre

A. Erhart

S. Fichtinger

M. Friedl

P. Garin

R. Gergen

C. Goupy

D. Hainz

D. Hauff

E. Jericha

M. Kaznacheeva

H. Kluck

T. Lasserre

D. Lhuillier

O. Litaize

P. Marcillac

R. Martin

E. Namuth

T. Ortmann

D. Poda

L. Peters

F. Reindl

W. Reindl

F. Rodari

J. Rothe

N. Schermer

J. Schieck

S. Schönert

C. Schwertner

G. Soum-Sidikov

R. Strauss

R. Thalmeier

L. Thulliez

C. Trunner

M. Vignati

M. Vivier

P. Wasser

A. Wex

The CRAB facility at the TU Wien TRIGA reactor: status and related physics program

The identification of jets originating from quarks and gluons, often referred to as quark/gluon tagging, plays an important role in various analyses performed at the Large Hadron Collider, as Standard Model measurements and searches for new particles decaying to quarks often rely on suppressing a large gluon-induced background. This paper describes the measurement of the efficiencies of quark/gluon taggers developed within the ATLAS Collaboration, using $\sqrt{s} = 13$ TeV proton–proton collision data with an integrated luminosity of 140 fb $^{-1}$ collected by the ATLAS experiment. Two taggers with high performances in rejecting jets from gluon over jets from quarks are studied: one tagger is based on requirements on the number of inner-detector tracks associated with the jet, and the other combines several jet substructure observables using a boosted decision tree. A method is established to determine the quark/gluon fraction in data, by using quark/gluon-enriched subsamples defined by the jet pseudorapidity. Differences in tagging efficiency between data and simulation are provided for jets with transverse momentum between 500 GeV and 2 TeV and for multiple tagger working points.

G. Aad

B. Abbott

K. Abeling

N.J. Abicht

S.H. Abidi

Morocco

A. Aboulhorma

Israel

H. Abramowicz

H. Abreu

Y. Abulaiti

United Kingdom

B.S. Acharya

C. Adam Bourdarios

Poland

L. Adamczyk

S.V. Addepalli

M.J. Addison

J. Adelman

A. Adiguzel

T. Adye

A.A. Affolder

Switzerland

Y. Afik

Spain

M.N. Agaras

J. Agarwala

A. Aggarwal

Romania

C. Agheorghiesei

A. Ahmad

Azerbaijan

F. Ahmadov

W.S. Ahmed

S. Ahuja

X. Ai

G. Aielli

A. Aikot

M. Ait Tamlihat

B. Aitbenchikh

I. Aizenberg

M. Akbiyik

Sweden

T.P.A. Åkesson

A.V. Akimov

Japan

D. Akiyama

N.N. Akolkar

K. Al Khoury

G.L. Alberghi

J. Albert

P. Albicocco

G.L. Albouy

Performance and calibration of quark/gluon-jet taggers using 140 fb$^{−1}$ of $\textit{pp}$ collisions at ${{\sqrt{\boldsymbol s}\bf = 13}}$ TeV with the ATLAS detector * We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; ANID, Chile; CAS, MOST and NSFC, China; Minciencias, Colombia; MEYS CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS and CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF and MPG, Germany; GSRI, Greece; RGC and Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MEiN, Poland; FCT, Portugal; MNE/IFA, Romania; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ, Slovenia; DSI/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taipei; TENMAK, Türkiye; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have received support from BCKDF, CANARIE, CRC and DRAC, Canada; PRIMUS 21/SCI/017 and UNCE SCI/013, Czech Republic; COST, ERC, ERDF, Horizon 2020, ICSC-Next Generation EU and Marie Skłodowska-Curie Actions, European Union; Investissements d'Avenir Labex, Investissements d'Avenir Idex and ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and MINERVA, Israel; Norwegian Financial Mechanism 2014-2021, Norway; NCN and NAWA, Poland; La Caixa Banking Foundation, CERCA Programme Generalitat de Catalunya and PROMETEO and GenT Programmes Generalitat Valenciana, Spain; Göran Gustafssons Stiftelse, Sweden; The Royal Society and Leverhulme Trust, United Kingdom.