Pub Date : 2021-05-18DOI: 10.21203/RS.3.RS-544214/V1
M. Aker, M. Bottcher, A. Beglarian, J. Behrens, A. Berlev, U. Besserer, B. Bieringer, F. Block, B. Bornschein, L. Bornschein, T. Brunst, T. Caldwell, R. Carney, L. L. Cascio, S. Chilingaryan, W. Choi, K. Debowski, M. Deffert, M. Descher, D. D. Barrero, P. Doe, O. Dragouns, G. Drexlin, K. Eitel, E. Ellinger, R. Engel, S. Enomoto, A. Felden, J. Formaggio, F. Frankle, G. Franklin, F. Friedel, A. Fulst, K. Gauda, W. Gil, F. Gluck, R. Grossle, R. Gumbsheimer, V. Gupta, T. Hohn, V. Hannen, N. Haussmann, K. Helbing, S. Hickford, R. Hiller, D. Hillsheimer, D. Hinz, T. Houdy, A. Huber, A. Jansen, C. Karl, F. Kellerer, J. Kellerer, M. Klein, C. Kohler, L. Kollenberger, A. Kopmann, M. Korzeczek, A. Kovalík, B. Krasch, H. Krause, N. Kunka, T. Lasserre, T. Le, O. Lebeda, B. Lehnert, A. Lokhov, M. Machatschek, E. Malcherek, M. Mark, A. Marsteller, E. Martín, C. Melzer, A. Menshikov, S. Mertens, S. Mertens, J. Mostafa, K. Muller, S. Niemes, P. Oelpmann, D. Parno, A. Poon, J. Poyato, F. Priester, M. Rollig, C. Rottele, R
We report the results of the second measurement campaign of the Karlsruhe Tritium Neutrino (KATRIN) experiment. KATRIN probes the effective electron anti-neutrino mass, mν, via a high-precision measurement of the tritium β-decay spectrum close to its endpoint at 18.6 keV. In the second physics run presented here, the source activity was increased by a factor of 3.8 and the background was reduced by 25% with respect to the first campaign. A sensitivity on mν of 0.7 eV/c2 at 90% confidence level (CL) was reached. This is the first sub-eV sensitivity from a direct neutrino-mass experiment. The best fit to the spectral data yields mν2=(0.26±0.34) eV2/c4, resulting in an upper limit of mν<0.9 eV/c2 (90% CL). By combining this result with the first neutrino mass campaign, we find an upper limit of mν<0.8 eV/c2 (90% CL).
{"title":"First direct neutrino-mass measurement with sub-eV sensitivity","authors":"M. Aker, M. Bottcher, A. Beglarian, J. Behrens, A. Berlev, U. Besserer, B. Bieringer, F. Block, B. Bornschein, L. Bornschein, T. Brunst, T. Caldwell, R. Carney, L. L. Cascio, S. Chilingaryan, W. Choi, K. Debowski, M. Deffert, M. Descher, D. D. Barrero, P. Doe, O. Dragouns, G. Drexlin, K. Eitel, E. Ellinger, R. Engel, S. Enomoto, A. Felden, J. Formaggio, F. Frankle, G. Franklin, F. Friedel, A. Fulst, K. Gauda, W. Gil, F. Gluck, R. Grossle, R. Gumbsheimer, V. Gupta, T. Hohn, V. Hannen, N. Haussmann, K. Helbing, S. Hickford, R. Hiller, D. Hillsheimer, D. Hinz, T. Houdy, A. Huber, A. Jansen, C. Karl, F. Kellerer, J. Kellerer, M. Klein, C. Kohler, L. Kollenberger, A. Kopmann, M. Korzeczek, A. Kovalík, B. Krasch, H. Krause, N. Kunka, T. Lasserre, T. Le, O. Lebeda, B. Lehnert, A. Lokhov, M. Machatschek, E. Malcherek, M. Mark, A. Marsteller, E. Martín, C. Melzer, A. Menshikov, S. Mertens, S. Mertens, J. Mostafa, K. Muller, S. Niemes, P. Oelpmann, D. Parno, A. Poon, J. Poyato, F. Priester, M. Rollig, C. Rottele, R","doi":"10.21203/RS.3.RS-544214/V1","DOIUrl":"https://doi.org/10.21203/RS.3.RS-544214/V1","url":null,"abstract":"\u0000 We report the results of the second measurement campaign of the Karlsruhe Tritium Neutrino (KATRIN) experiment. KATRIN probes the effective electron anti-neutrino mass, mν, via a high-precision measurement of the tritium β-decay spectrum close\u0000to its endpoint at 18.6 keV. In the second physics run presented here, the source activity was increased by a factor of 3.8 and\u0000the background was reduced by 25% with respect to the first campaign. A sensitivity on mν of 0.7 eV/c2 at 90% confidence level (CL) was reached. This is the first sub-eV sensitivity from a direct neutrino-mass experiment. The best fit to the spectral data yields mν2=(0.26±0.34) eV2/c4, resulting in an upper limit of mν<0.9 eV/c2 (90% CL). By combining this result with the first neutrino mass campaign, we find an upper limit of mν<0.8 eV/c2 (90% CL).","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80441290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-17DOI: 10.1103/PhysRevD.103.102004
D. Alesini, C. Braggio, G. Carugno, N. Crescini, D. D'Agostino, D. Di Gioacchino, R. Di Vora, P. Falferi, U. Gambardella, C. Gatti, G. Iannone, C. Ligi, A. Lombardi, G. Maccarrone, A. Ortolan, R. Pengo, A. Rettaroli, G. Ruoso, L. Taffarello, S. Tocci
An haloscope of the QUAX--$agamma$ experiment composed of an OFHC-Cu cavity inside an 8.1 T magnet and cooled to $sim200$ mK was put in operation for the search of galactic axion with mass $m_asimeq43~mutext{eV}$. The power emitted by the resonant cavity was amplified with a Josephson Parametric Amplifier whose noise fluctuations are at the Standard Quantum Limit (SQL). With the data collected in about 1 h at the cavity frequency $nu_c=10.40176$ GHz the experiment reached the sensitivity necessary for the detection of galactic QCD-axion setting the $90%$ confidence level (CL) limit to the axion-photon coupling $g_{agammagamma}<0.639cdot10^{-13}$ GeV$^{-1}$.
{"title":"Search for invisible axion dark matter of mass \u0000ma=43 μeV\u0000 with the QUAX–\u0000aγ\u0000 experiment","authors":"D. Alesini, C. Braggio, G. Carugno, N. Crescini, D. D'Agostino, D. Di Gioacchino, R. Di Vora, P. Falferi, U. Gambardella, C. Gatti, G. Iannone, C. Ligi, A. Lombardi, G. Maccarrone, A. Ortolan, R. Pengo, A. Rettaroli, G. Ruoso, L. Taffarello, S. Tocci","doi":"10.1103/PhysRevD.103.102004","DOIUrl":"https://doi.org/10.1103/PhysRevD.103.102004","url":null,"abstract":"An haloscope of the QUAX--$agamma$ experiment composed of an OFHC-Cu cavity inside an 8.1 T magnet and cooled to $sim200$ mK was put in operation for the search of galactic axion with mass $m_asimeq43~mutext{eV}$. The power emitted by the resonant cavity was amplified with a Josephson Parametric Amplifier whose noise fluctuations are at the Standard Quantum Limit (SQL). With the data collected in about 1 h at the cavity frequency $nu_c=10.40176$ GHz the experiment reached the sensitivity necessary for the detection of galactic QCD-axion setting the $90%$ confidence level (CL) limit to the axion-photon coupling $g_{agammagamma}<0.639cdot10^{-13}$ GeV$^{-1}$.","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79476584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Oshima, T. Matsuo, Aidy Ali, S. Aoki, L. Berns, T. Fukuda, Y. Hanaoka, Y. Hayato, A. Hiramoto, A. Ichikawa, H. Kawahara, T. Kikawa, R. Komatani, M. Komatsu, K. Kuretsubo, T. Marushima, H. Matsumoto, S. Mikado, A. Minamino, K. Mizuno, Y. Morimoto, K. Morishima, N. Naganawa, M. Naiki, M. Nakamura, Y. Nakamura, N. Nakano, T. Nakano, T. Nakaya, A. Nishio, T. Odagawa, S. Ogawa, H. Rokujo, O. Sato, H. Shibuya, K. Sugimura, L. Suzui, Y. Suzuki, H. Takagi, S. Takahashi, T. Takao, Y. Tanihara, R. Watanabe, K. Yamada, K. Yasutome, M. Yokoyama
We report the flux-averaged $nu_{mu}$ charged-current cross sections on iron using an emulsion-based detector exposed to the T2K neutrino beam in the J-PARC neutrino facility. The data samples correspond to 4.0$times$10$^{19}$ protons on target, and the neutrino mean energy is 1.49$,$GeV. The cross section was measured to be $sigma^{mathrm{Fe}}_{mathrm{CC}} = (1.28 pm 0.11({mathrm{stat.}})^{+0.12}_{-0.11}({mathrm{syst.}})) times 10^{-38} , {mathrm{cm}}^{2}/{mathrm{nucleon}}$. The cross section in a limited kinematic phase space of induced muons, $theta_{mu} 400 , {rm MeV}/c$, on iron was $sigma^{mathrm{Fe}}_{mathrm{CC hspace{1mm} phase hspace{0.5mm} space}} = (0.84 pm 0.07({mathrm{stat.}})^{+0.07}_{-0.06}({mathrm{syst.}})) times 10^{-38} , {mathrm{cm}}^{2}/{mathrm{nucleon}}$. These results are consistent with previous values obtained via different techniques using the same beamline, and it is well reproduced by current neutrino interaction models. These results represent a significant advance for precise measurements of the neutrino-nucleus interactions around the 1$,$GeV energy region.
{"title":"First measurement using a nuclear emulsion detector of the ν\u0000 μ charged-current cross section on iron around the 1 GeV energy region","authors":"H. Oshima, T. Matsuo, Aidy Ali, S. Aoki, L. Berns, T. Fukuda, Y. Hanaoka, Y. Hayato, A. Hiramoto, A. Ichikawa, H. Kawahara, T. Kikawa, R. Komatani, M. Komatsu, K. Kuretsubo, T. Marushima, H. Matsumoto, S. Mikado, A. Minamino, K. Mizuno, Y. Morimoto, K. Morishima, N. Naganawa, M. Naiki, M. Nakamura, Y. Nakamura, N. Nakano, T. Nakano, T. Nakaya, A. Nishio, T. Odagawa, S. Ogawa, H. Rokujo, O. Sato, H. Shibuya, K. Sugimura, L. Suzui, Y. Suzuki, H. Takagi, S. Takahashi, T. Takao, Y. Tanihara, R. Watanabe, K. Yamada, K. Yasutome, M. Yokoyama","doi":"10.1093/PTEP/PTAB027","DOIUrl":"https://doi.org/10.1093/PTEP/PTAB027","url":null,"abstract":"We report the flux-averaged $nu_{mu}$ charged-current cross sections on iron using an emulsion-based detector exposed to the T2K neutrino beam in the J-PARC neutrino facility. The data samples correspond to 4.0$times$10$^{19}$ protons on target, and the neutrino mean energy is 1.49$,$GeV. The cross section was measured to be $sigma^{mathrm{Fe}}_{mathrm{CC}} = (1.28 pm 0.11({mathrm{stat.}})^{+0.12}_{-0.11}({mathrm{syst.}})) times 10^{-38} , {mathrm{cm}}^{2}/{mathrm{nucleon}}$. The cross section in a limited kinematic phase space of induced muons, $theta_{mu} 400 , {rm MeV}/c$, on iron was $sigma^{mathrm{Fe}}_{mathrm{CC hspace{1mm} phase hspace{0.5mm} space}} = (0.84 pm 0.07({mathrm{stat.}})^{+0.07}_{-0.06}({mathrm{syst.}})) times 10^{-38} , {mathrm{cm}}^{2}/{mathrm{nucleon}}$. These results are consistent with previous values obtained via different techniques using the same beamline, and it is well reproduced by current neutrino interaction models. These results represent a significant advance for precise measurements of the neutrino-nucleus interactions around the 1$,$GeV energy region.","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91274140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Prompt and nonprompt productions of exotic multiquark states are studied using the $sim$10.4 fb$^{-1}$ data sample collected by the D0 experiment in Tevatron $pbar{p}$ collisions at $sqrt{s}$ = 1.96 TeV. The recent D0 results on the prompt and nonprompt production of the $X(3872)$ and $Z_c^+(3900)$ states and the $P_c$ pentaquarks at the 4450 MeV region are reported. Signals corresponding to these states are found in the nonprompt production, whereas only the $X(3872)$ state is seen in the prompt production. The ratio of prompt to nonprompt $X(3872)$ production is about three times larger in the D0 measurement than that obtained by the ATLAS experiment at 8 TeV. Theoretically, the production, formation, coalescence, and disassociation processes are expected to be quite different for conventional mesons with a spatial size of (0.4-0.8) fm, compact multiquark states such as tetraquarks with a size of a few fm, and spatially extended molecular states with a size of (4-10) fm. They can be differently affected in prompt hadron-hadron collisions where there are many additional particles emitted from the interaction point. Consequently, the prompt to nonprompt production ratio of spatially extended exotic states can be suppressed at LHC comparing with the Tevatron conditions, because of large difference in the hadron-hadron collisions particle multiplicity. The prompt production studies provide an opportunity to better understand the nature of exotic states.
{"title":"Latest D0 results on exotic hadrons produced in $pbar p $ collision","authors":"A. Drutskoy","doi":"10.22323/1.390.0371","DOIUrl":"https://doi.org/10.22323/1.390.0371","url":null,"abstract":"Prompt and nonprompt productions of exotic multiquark states are studied using the $sim$10.4 fb$^{-1}$ data sample collected by the D0 experiment in Tevatron $pbar{p}$ collisions at $sqrt{s}$ = 1.96 TeV. The recent D0 results on the prompt and nonprompt production of the $X(3872)$ and $Z_c^+(3900)$ states and the $P_c$ pentaquarks at the 4450 MeV region are reported. Signals corresponding to these states are found in the nonprompt production, whereas only the $X(3872)$ state is seen in the prompt production. The ratio of prompt to nonprompt $X(3872)$ production is about three times larger in the D0 measurement than that obtained by the ATLAS experiment at 8 TeV. Theoretically, the production, formation, coalescence, and disassociation processes are expected to be quite different for conventional mesons with a spatial size of (0.4-0.8) fm, compact multiquark states such as tetraquarks with a size of a few fm, and spatially extended molecular states with a size of (4-10) fm. They can be differently affected in prompt hadron-hadron collisions where there are many additional particles emitted from the interaction point. Consequently, the prompt to nonprompt production ratio of spatially extended exotic states can be suppressed at LHC comparing with the Tevatron conditions, because of large difference in the hadron-hadron collisions particle multiplicity. The prompt production studies provide an opportunity to better understand the nature of exotic states.","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76997510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-30DOI: 10.1103/PHYSREVD.103.055004
Younggeun Kim, S. Youn, Danho Ahn, Junu Jung, Dongok Kim, Y. Semertzidis
Analogous to the light-shining-through-wall setup proposed for axion-like particle searches, a pair of resonant cavities have been considered to search for an extra U(1) massive gauge boson, called a hidden photon, which mediates the interactions in the hidden sector. We propose a new cavity configuration, consisting of a cylindrical emitter surrounded by a hollow cylindrical detector to remarkably improve experimental sensitivity to hidden photon signals in the $mu$eV mass range. An extensive study was conducted to find the optimal cavity geometry and resonant mode, which yields the best performance. In addition, a feasible application of superconducting RF technology was explored. We found the integration of these potential improvements will enhance the sensitivity to the effective kinetic mixing parameter between the hidden photon and the Standard Model photon by multiple orders of magnitude.
{"title":"Sensitivity improvement in hidden photon detection using resonant cavities","authors":"Younggeun Kim, S. Youn, Danho Ahn, Junu Jung, Dongok Kim, Y. Semertzidis","doi":"10.1103/PHYSREVD.103.055004","DOIUrl":"https://doi.org/10.1103/PHYSREVD.103.055004","url":null,"abstract":"Analogous to the light-shining-through-wall setup proposed for axion-like particle searches, a pair of resonant cavities have been considered to search for an extra U(1) massive gauge boson, called a hidden photon, which mediates the interactions in the hidden sector. We propose a new cavity configuration, consisting of a cylindrical emitter surrounded by a hollow cylindrical detector to remarkably improve experimental sensitivity to hidden photon signals in the $mu$eV mass range. An extensive study was conducted to find the optimal cavity geometry and resonant mode, which yields the best performance. In addition, a feasible application of superconducting RF technology was explored. We found the integration of these potential improvements will enhance the sensitivity to the effective kinetic mixing parameter between the hidden photon and the Standard Model photon by multiple orders of magnitude.","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81740412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-28DOI: 10.1103/PHYSREVD.103.052009
U. Acharya, C. Aidala, Y. Akiba, M. Alfred, V. Andrieux, N. Apadula, H. Asano, B. Azmoun, V. Babintsev, N. Bandara, K. Barish, S. Bathe, A. Bazilevsky, M. Beaumier, R. Belmont, A. Berdnikov, Y. Berdnikov, L. Bichon, B. Blankenship, D. Blau, J. Bok, V. Borisov, M. Brooks, J. Bryslawskyj, V. Bumazhnov, Sarah Campbell, V. Canoa Roman, R. Cervantes, C. Chi, M. Chiu, I. Choi, J. B. Choi, Z. Citron, M. Connors, R. Corliss, N. Cronin, M. Csanád, T. Csörgő, T. Danley, M. Daugherity, G. David, K. DeBlasio, K. Dehmelt, A. Denisov, A. Deshpande, E. Desmond, A. Dion, D. Dixit, J. Do, A. Drees, K. Drees, J. Durham, A. Durum, A. Enokizono, H. En’yo, R. Esha, S. Esumi, B. Fadem, W. Fan, N. Feege, D. Fields, M. Finger, D. Firak, D. Fitzgerald, S. Fokin, J. Frantz, A. Franz, A. Frawley, Y. Fukuda, C. Gal, P. Gallus, P. Garg, H. Ge, M. Giles, F. Giordano, Y. Goto, N. Grau, S. Greene, M. Grosse Perdekamp, T. Gunji, H. Guragain, T. Hachiya, J. Haggerty, K. Hahn, H. Hamagaki, H. Hamilton, S. Y. Han, J. Hanks, S. Hasegawa, T.
We present a measurement of the transverse single-spin asymmetry for $pi^0$ and $eta$ mesons in $p^uparrow$$+$$p$ collisions in the pseudorapidity range $|eta|<0.35$ and at a center-of-mass energy of 200 GeV with the PHENIX detector at the Relativistic Heavy Ion Collider. In comparison with previous measurements in this kinematic region, these results have a factor of 3 smaller uncertainties. As hadrons, $pi^0$ and $eta$ mesons are sensitive to both initial- and final-state nonperturbative effects for a mix of parton flavors. Comparisons of the differences in their transverse single-spin asymmetries have the potential to disentangle the possible effects of strangeness, isospin, or mass. These results can constrain the twist-3 trigluon collinear correlation function as well as the gluon Sivers function.
{"title":"Transverse single-spin asymmetries of midrapidity \u0000π0\u0000 and \u0000η\u0000 mesons in polarized \u0000p+p\u0000 collisions at \u0000s=200 GeV","authors":"U. Acharya, C. Aidala, Y. Akiba, M. Alfred, V. Andrieux, N. Apadula, H. Asano, B. Azmoun, V. Babintsev, N. Bandara, K. Barish, S. Bathe, A. Bazilevsky, M. Beaumier, R. Belmont, A. Berdnikov, Y. Berdnikov, L. Bichon, B. Blankenship, D. Blau, J. Bok, V. Borisov, M. Brooks, J. Bryslawskyj, V. Bumazhnov, Sarah Campbell, V. Canoa Roman, R. Cervantes, C. Chi, M. Chiu, I. Choi, J. B. Choi, Z. Citron, M. Connors, R. Corliss, N. Cronin, M. Csanád, T. Csörgő, T. Danley, M. Daugherity, G. David, K. DeBlasio, K. Dehmelt, A. Denisov, A. Deshpande, E. Desmond, A. Dion, D. Dixit, J. Do, A. Drees, K. Drees, J. Durham, A. Durum, A. Enokizono, H. En’yo, R. Esha, S. Esumi, B. Fadem, W. Fan, N. Feege, D. Fields, M. Finger, D. Firak, D. Fitzgerald, S. Fokin, J. Frantz, A. Franz, A. Frawley, Y. Fukuda, C. Gal, P. Gallus, P. Garg, H. Ge, M. Giles, F. Giordano, Y. Goto, N. Grau, S. Greene, M. Grosse Perdekamp, T. Gunji, H. Guragain, T. Hachiya, J. Haggerty, K. Hahn, H. Hamagaki, H. Hamilton, S. Y. Han, J. Hanks, S. Hasegawa, T. ","doi":"10.1103/PHYSREVD.103.052009","DOIUrl":"https://doi.org/10.1103/PHYSREVD.103.052009","url":null,"abstract":"We present a measurement of the transverse single-spin asymmetry for $pi^0$ and $eta$ mesons in $p^uparrow$$+$$p$ collisions in the pseudorapidity range $|eta|<0.35$ and at a center-of-mass energy of 200 GeV with the PHENIX detector at the Relativistic Heavy Ion Collider. In comparison with previous measurements in this kinematic region, these results have a factor of 3 smaller uncertainties. As hadrons, $pi^0$ and $eta$ mesons are sensitive to both initial- and final-state nonperturbative effects for a mix of parton flavors. Comparisons of the differences in their transverse single-spin asymmetries have the potential to disentangle the possible effects of strangeness, isospin, or mass. These results can constrain the twist-3 trigluon collinear correlation function as well as the gluon Sivers function.","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87599881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-16DOI: 10.1103/PhysRevD.103.092005
B. C. M. Ablikim, M. Achasov, P. Adlarson, S. Ahmed, M. Albrecht, A. Amoroso, Q. An, X. Bai, Y. Bai, O. Bakina, R. Ferroli, I. Balossino, Y. Ban, K. Begzsuren, J. Bennett, N. Berger, M. Bertani, D. Bettoni, F. Bianchi, J. Biernat, J. Bloms, A. Bortone, I. Boyko, R. Briere, H. Cai, X. Cai, A. Calcaterra, G. Cao, N. Cao, S. Cetin, J. Chang, W. Chang, G. Chelkov, D. Chen, G. Chen, H. Chen, M. Chen, S. Chen, X. Chen, Y. Chen, Z. Chen, W. Cheng, G. Cibinetto, F. Cossio, X. Cui, H. Dai, J. Dai, X. Dai, A. Dbeyssi, R. Boer, D. Dedovich, Z. Deng, A. Denig, I. Denysenko, M. Destefanis, F. DeMori, Y. Ding, C. Dong, J. Dong, L. Dong, M. Dong, S. Du, J. Fang, S. Fang, Y. Fang, R. Farinelli, L. Fava, F. Feldbauer, G. Felici, C. Feng, M. Fritsch, C. Fu, Y. Fu, X. Gao, Y. Gao, Y. Gao, I. Garzia, E. Gersabeck, A. Gilman, K. Goetzen, L. Gong, W. Gong, W. Gradl, M. Greco, L. Gu, M. Gu, S. Gu, Y. Gu, C. Guan, A. Guo, L. Guo, R. Guo, Y. Guo, A. Guskov, S. Han, T. Han, T. Han, X. Hao, F. Harris, N. Husken, K. He, F. Heinsius,
The rare decay $eta' to pi^+ pi^- e^+ e^-$ is studied using a sample of $1.3 times 10^9$ $J/psi$ events collected with the BESIII detector at BEPCII in 2009 and 2012. The branching fraction is measured with improved precision to be $left( 2.42pm0.05_{stat.}pm0.08_{syst.} right) times 10^{-3}$. In addition, the CP-violating asymmetry in the angle between the decay planes of the $pi^+pi^-$-pair and the $e^+e^-$-pair is investigated. A measurable value would indicate physics beyond the standard model; the result is $mathcal{A}_{CP} = left(1.6pm2.0_{stat.}pm0.6_{syst.} right)%$, which is consistent with the standard model expectation of no CP-violation. The precision is comparable to the asymmetry measurement in the $K^0_Ltopi^+pi^-e^+e^-$ decay where the observed $(14pm2)%$ effect is driven by a standard model mechanism.
利用2009年和2012年在BEPCII的BESIII探测器收集的$1.3 times 10^9$$J/psi$事件样本研究了罕见的衰变$eta' to pi^+ pi^- e^+ e^-$。分支分数测量精度提高为$left( 2.42pm0.05_{stat.}pm0.08_{syst.} right) times 10^{-3}$。此外，还研究了$pi^+pi^-$ -对和$e^+e^-$ -对衰减面夹角的cp违反不对称性。一个可测量的值将表明超出标准模型的物理;结果为$mathcal{A}_{CP} = left(1.6pm2.0_{stat.}pm0.6_{syst.} right)%$，符合不违反cp的标准模型期望。其精度可与$K^0_Ltopi^+pi^-e^+e^-$衰变中的不对称测量相媲美，其中观察到的$(14pm2)%$效应是由标准模型机制驱动的。
{"title":"Measurement of the branching fraction of and search for a \u0000CP\u0000-violating asymmetry in \u0000η′→π+π−e+e−\u0000 at BESIII","authors":"B. C. M. Ablikim, M. Achasov, P. Adlarson, S. Ahmed, M. Albrecht, A. Amoroso, Q. An, X. Bai, Y. Bai, O. Bakina, R. Ferroli, I. Balossino, Y. Ban, K. Begzsuren, J. Bennett, N. Berger, M. Bertani, D. Bettoni, F. Bianchi, J. Biernat, J. Bloms, A. Bortone, I. Boyko, R. Briere, H. Cai, X. Cai, A. Calcaterra, G. Cao, N. Cao, S. Cetin, J. Chang, W. Chang, G. Chelkov, D. Chen, G. Chen, H. Chen, M. Chen, S. Chen, X. Chen, Y. Chen, Z. Chen, W. Cheng, G. Cibinetto, F. Cossio, X. Cui, H. Dai, J. Dai, X. Dai, A. Dbeyssi, R. Boer, D. Dedovich, Z. Deng, A. Denig, I. Denysenko, M. Destefanis, F. DeMori, Y. Ding, C. Dong, J. Dong, L. Dong, M. Dong, S. Du, J. Fang, S. Fang, Y. Fang, R. Farinelli, L. Fava, F. Feldbauer, G. Felici, C. Feng, M. Fritsch, C. Fu, Y. Fu, X. Gao, Y. Gao, Y. Gao, I. Garzia, E. Gersabeck, A. Gilman, K. Goetzen, L. Gong, W. Gong, W. Gradl, M. Greco, L. Gu, M. Gu, S. Gu, Y. Gu, C. Guan, A. Guo, L. Guo, R. Guo, Y. Guo, A. Guskov, S. Han, T. Han, T. Han, X. Hao, F. Harris, N. Husken, K. He, F. Heinsius,","doi":"10.1103/PhysRevD.103.092005","DOIUrl":"https://doi.org/10.1103/PhysRevD.103.092005","url":null,"abstract":"The rare decay $eta' to pi^+ pi^- e^+ e^-$ is studied using a sample of $1.3 times 10^9$ $J/psi$ events collected with the BESIII detector at BEPCII in 2009 and 2012. The branching fraction is measured with improved precision to be $left( 2.42pm0.05_{stat.}pm0.08_{syst.} right) times 10^{-3}$. In addition, the CP-violating asymmetry in the angle between the decay planes of the $pi^+pi^-$-pair and the $e^+e^-$-pair is investigated. A measurable value would indicate physics beyond the standard model; the result is $mathcal{A}_{CP} = left(1.6pm2.0_{stat.}pm0.6_{syst.} right)%$, which is consistent with the standard model expectation of no CP-violation. The precision is comparable to the asymmetry measurement in the $K^0_Ltopi^+pi^-e^+e^-$ decay where the observed $(14pm2)%$ effect is driven by a standard model mechanism.","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78395454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recent measurements based on jet production in high energy pp collisions at the CERN LHC with the CMS detector are reported. Specifically, the measurement of the inclusive jet production cross section as a function of the anti-$k_t$ distance parameter $R$ divided by the jet cross section at $R = 0.4$, is discussed. The cross section ratio is sensitive to various perturbative and non-perturbative treatments of the jet formation process in quantum chromodynamics (QCD). In the second study, the regimes of validity of the parton shower and matrix element approaches are tested on multijet events in pp collisions at $sqrt{s} = 8$ and $13$ TeV. Special attention is given to the second and third leading $p_text{T}$ jets and their momenta and rapidity-azimuth correlations. Finally, studies of dijet production where the two leading $p_T$ jets are separated by a large pseudorapidity interval void of charged particles is presented. This signature is expected from hard color singlet exchange (two-gluon exchange in perturbative QCD). The latter can be treated with perturbative QCD techniques based on the Balitsky-Fadin-Kuraev-Lipatov (BFKL) evolution equations.
{"title":"Jet measurements at CMS","authors":"C. Baldenegro","doi":"10.22323/1.390.0451","DOIUrl":"https://doi.org/10.22323/1.390.0451","url":null,"abstract":"Recent measurements based on jet production in high energy pp collisions at the CERN LHC with the CMS detector are reported. Specifically, the measurement of the inclusive jet production cross section as a function of the anti-$k_t$ distance parameter $R$ divided by the jet cross section at $R = 0.4$, is discussed. The cross section ratio is sensitive to various perturbative and non-perturbative treatments of the jet formation process in quantum chromodynamics (QCD). In the second study, the regimes of validity of the parton shower and matrix element approaches are tested on multijet events in pp collisions at $sqrt{s} = 8$ and $13$ TeV. Special attention is given to the second and third leading $p_text{T}$ jets and their momenta and rapidity-azimuth correlations. Finally, studies of dijet production where the two leading $p_T$ jets are separated by a large pseudorapidity interval void of charged particles is presented. This signature is expected from hard color singlet exchange (two-gluon exchange in perturbative QCD). The latter can be treated with perturbative QCD techniques based on the Balitsky-Fadin-Kuraev-Lipatov (BFKL) evolution equations.","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75201012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-03DOI: 10.1103/PhysRevD.103.116028
Julian Collado, J. Howard, Taylor Faucett, Tony Tong, P. Baldi, D. Whiteson
We investigate whether state-of-the-art classification features commonly used to distinguish electrons from jet backgrounds in collider experiments are overlooking valuable information. A deep convolutional neural network analysis of electromagnetic and hadronic calorimeter deposits is compared to the performance of typical features, revealing a $approx 5%$ gap which indicates that these lower-level data do contain untapped classification power. To reveal the nature of this unused information, we use a recently developed technique to map the deep network into a space of physically interpretable observables. We identify two simple calorimeter observables which are not typically used for electron identification, but which mimic the decisions of the convolutional network and nearly close the performance gap.
{"title":"Learning to identify electrons","authors":"Julian Collado, J. Howard, Taylor Faucett, Tony Tong, P. Baldi, D. Whiteson","doi":"10.1103/PhysRevD.103.116028","DOIUrl":"https://doi.org/10.1103/PhysRevD.103.116028","url":null,"abstract":"We investigate whether state-of-the-art classification features commonly used to distinguish electrons from jet backgrounds in collider experiments are overlooking valuable information. A deep convolutional neural network analysis of electromagnetic and hadronic calorimeter deposits is compared to the performance of typical features, revealing a $approx 5%$ gap which indicates that these lower-level data do contain untapped classification power. To reveal the nature of this unused information, we use a recently developed technique to map the deep network into a space of physically interpretable observables. We identify two simple calorimeter observables which are not typically used for electron identification, but which mimic the decisions of the convolutional network and nearly close the performance gap.","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86548146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-02DOI: 10.1103/PhysRevD.105.L111101
Z. Atif, J. Choi, B. Han, C. Jang, H. Jang, J. Jang, E. Jeon, S. Jeon, K. Joo, K. Ju, D. Jung, H. Kim, H. Kim, J. G. Kim, J. Kim, B. R. Kim, J. Kim, S. Kim, S. Y. Kim, W. Kim, Y. Kim, Y. Ko, E. Kwon, D. H. Lee, H. Lee, J. Lee, J. Lee, M. H. Lee, Y. Oh, I. Lim, D. Moon, H. Park, H. Park, K. Park, M. Pac, H. Seo, J. Seo, K. Seo, C. Shin, K. Siyeon, G. Sun, B. Yang, J. Yoo, S. Yoon, I. Yeo, I. Yu
We present a model independent search for sterile neutrino oscillation using 2,508.9,days of RENO near detector data and a NEOS published result. The reactor related systematic uncertainties are significantly suppressed as both detectors are located at the same reactor complex of Hanbit Nuclear Power Plant. The search is performed by electron antineutrino ($overline{nu}_e$) disappearance between six reactors and two detectors with baselines of 294,m (RENO) and 24,m (NEOS). A spectral comparison of the NEOS prompt-energy spectrum with a prediction from the RENO measurement can explore reactor $overline{nu}_e$ oscillations to sterile neutrino. Based on the spectral comparison, we obtain a 90% C.L. excluded region of $10^{-3}<|Delta m_{41}^2|<7$,eV$^2$. We also obtain a 68% C.L. allowed region with the best fit of $|Delta m_{41}^2|=2.37,pm,0.03,$,eV$^2$ and $sin^2 2theta_{14}$=0.09$,pm,$0.03. Comparisons of obtained reactor antineutrino spectra at reactor sources are made among RENO, NEOS and Daya Bay to find a possible spectral variation. The unfolded reactor antineutrino spectra will be useful for studying reactor neutrino physics and particle physics beyond the Standard Model.
{"title":"Search for sterile neutrino oscillation using RENO and NEOS data.","authors":"Z. Atif, J. Choi, B. Han, C. Jang, H. Jang, J. Jang, E. Jeon, S. Jeon, K. Joo, K. Ju, D. Jung, H. Kim, H. Kim, J. G. Kim, J. Kim, B. R. Kim, J. Kim, S. Kim, S. Y. Kim, W. Kim, Y. Kim, Y. Ko, E. Kwon, D. H. Lee, H. Lee, J. Lee, J. Lee, M. H. Lee, Y. Oh, I. Lim, D. Moon, H. Park, H. Park, K. Park, M. Pac, H. Seo, J. Seo, K. Seo, C. Shin, K. Siyeon, G. Sun, B. Yang, J. Yoo, S. Yoon, I. Yeo, I. Yu","doi":"10.1103/PhysRevD.105.L111101","DOIUrl":"https://doi.org/10.1103/PhysRevD.105.L111101","url":null,"abstract":"We present a model independent search for sterile neutrino oscillation using 2,508.9,days of RENO near detector data and a NEOS published result. The reactor related systematic uncertainties are significantly suppressed as both detectors are located at the same reactor complex of Hanbit Nuclear Power Plant. The search is performed by electron antineutrino ($overline{nu}_e$) disappearance between six reactors and two detectors with baselines of 294,m (RENO) and 24,m (NEOS). A spectral comparison of the NEOS prompt-energy spectrum with a prediction from the RENO measurement can explore reactor $overline{nu}_e$ oscillations to sterile neutrino. Based on the spectral comparison, we obtain a 90% C.L. excluded region of $10^{-3}<|Delta m_{41}^2|<7$,eV$^2$. We also obtain a 68% C.L. allowed region with the best fit of $|Delta m_{41}^2|=2.37,pm,0.03,$,eV$^2$ and $sin^2 2theta_{14}$=0.09$,pm,$0.03. Comparisons of obtained reactor antineutrino spectra at reactor sources are made among RENO, NEOS and Daya Bay to find a possible spectral variation. The unfolded reactor antineutrino spectra will be useful for studying reactor neutrino physics and particle physics beyond the Standard Model.","PeriodicalId":8429,"journal":{"name":"arXiv: High Energy Physics - Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80200436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：