Author:
Aprile E.,Abe K.,Agostini F.,Ahmed Maouloud S.,Alfonsi M.,Althueser L.,Andrieu B.,Angelino E.,Angevaare J. R.,Antochi V. C.,Antón Martin D.,Arneodo F.,Baudis L.,Baxter A. L.,Bellagamba L.,Biondi R.,Bismark A.,Brown A.,Bruenner S.,Bruno G.,Budnik R.,Bui T. K.,Cai C.,Capelli C.,Cardoso J. M. R.,Cichon D.,Colijn A. P.,Conrad J.,Cuenca-García J. J.,Cussonneau J. P.,D’Andrea V.,Decowski M. P.,Di Gangi P.,Di Pede S.,Diglio S.,Eitel K.,Elykov A.,Farrell S.,Ferella A. D.,Ferrari C.,Fischer H.,Fulgione W.,Gaemers P.,Gaior R.,Gallo Rosso A.,Galloway M.,Gao F.,Glade-Beucke R.,Grandi L.,Grigat J.,Guida M.,Hammann R.,Higuera A.,Hils C.,Hoetzsch L.,Howlett J.,Iacovacci M.,Itow Y.,Jakob J.,Joerg F.,Joy A.,Kato N.,Kara M.,Kavrigin P.,Kazama S.,Kobayashi M.,Koltman G.,Kopec A.,Kuger F.,Landsman H.,Lang R. F.,Levinson L.,Li I.,Li S.,Liang S.,Lindemann S.,Lindner M.,Liu K.,Loizeau J.,Lombardi F.,Long J.,Lopes J. A. M.,Ma Y.,Macolino C.,Mahlstedt J.,Mancuso A.,Manenti L.,Marignetti F.,Marrodán Undagoitia T.,Martens K.,Masbou J.,Masson D.,Masson E.,Mastroianni S.,Messina M.,Miuchi K.,Mizukoshi K.,Molinario A.,Moriyama S.,Morå K.,Mosbacher Y.,Murra M.,Müller J.,Ni K.,Oberlack U.,Paetsch B.,Palacio J.,Peres R.,Peters C.,Pienaar J.,Pierre M.,Pizzella V.,Plante G.,Qi J.,Qin J.,Ramírez García D.,Reichard S.,Rocchetti A.,Rupp N.,Sanchez L.,Sanchez-Lucas P.,Santos J. M. F. dos,Sarnoff I.,Sartorelli G.,Schreiner J.,Schulte D.,Schulte P.,Schulze Eißing H.,Schumann M.,Lavina L. Scotto,Selvi M.,Semeria F.,Shagin P.,Shi S.,Shockley E.,Silva M.,Simgen H.,Takeda A.,Tan P.-L.,Terliuk A.,Thers D.,Toschi F.,Trinchero G.,Tunnell C.,Tönnies F.,Valerius K.,Volta G.,Weinheimer C.,Weiss M.,Wenz D.,Wittweg C.,Wolf T.,Xu D.,Xu Z.,Yamashita M.,Yang L.,Ye J.,Yuan L.,Zavattini G.,Zerbo S.,Zhong M.,Zhu T.,Geppert C.,Riemer J.,
Abstract
AbstractA low-energy electronic recoil calibration of XENON1T, a dual-phase xenon time projection chamber, with an internal $${}^{37}$$
37
Ar source was performed. This calibration source features a 35-day half-life and provides two mono-energetic lines at 2.82 keV and 0.27 keV. The photon yield and electron yield at 2.82 keV are measured to be ($$32.3\,\pm \,0.3$$
32.3
±
0.3
) photons/keV and ($$40.6\,\pm \,0.5$$
40.6
±
0.5
) electrons/keV, respectively, in agreement with other measurements and with NEST predictions. The electron yield at 0.27 keV is also measured and it is ($$68.0^{+6.3}_{-3.7}$$
68
.
0
-
3.7
+
6.3
) electrons/keV. The $${}^{37}$$
37
Ar calibration confirms that the detector is well-understood in the energy region close to the detection threshold, with the 2.82 keV line reconstructed at ($$2.83\,\pm \,0.02$$
2.83
±
0.02
) keV, which further validates the model used to interpret the low-energy electronic recoil excess previously reported by XENON1T. The ability to efficiently remove argon with cryogenic distillation after the calibration proves that $${}^{37}$$
37
Ar can be considered as a regular calibration source for multi-tonne xenon detectors.