A Search for Neutrino-less Double Beta Decay with nEXO

用 nEXO 寻找无中微子双贝塔衰变

• 批准号: 1812245
• 负责人: Andrea Pocar
• 金额: $ 75万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1812245&HistoricalAwards=false
• 关键词: Search; Neutrino; less; Double; Beta

One fundamental question in science today is why the Universe and everything in it is made almost exclusively of matter and essentially no anti-matter when the equations describing Nature lead us to expect a nearly equal amount of matter and anti-matter. This award supports investigations at the University of Massachusetts, Amherst into one possible origin of this imbalance through the study of whether the lightest fundamental particle in Nature, the neutrino, is made of both matter and anti-matter. If this is the case, a very rare nuclear process known as neutrino-less double beta decay is possible. This decay, in which a nucleus transforms into another by emitting two electrons and nothing else, would unambiguously determine that neutrinos and anti-neutrinos are the same particle, i.e. that they are Majorana particles. The work at UMass Amherst focuses on key R&D aspects for the design of the detector for the nEXO experiment, with research carried out in the lab with postdocs and students (graduate and undergraduate), in an academic, research-intensive environment. The PI and his group are also involved in operating and analyzing the data of the EXO-200 experiment, a smaller scale nEXO predecessor running in New Mexico and holding one of the best sensitivities for neutrino-less double beta decay to date. The activities supported by this award train human resources of diverse backgrounds and develop technologies that align with strategic sectors for the US, such as data science and artificial intelligence, nuclear medicine and non-proliferation, and national security programs at national laboratories. The UMass Amherst particle astrophysics group has a record of excellence and diversity for undergraduate involvement in research, and the Amherst Center for Fundamental Interactions (ACFI) actively contributes to promoting the physics related to this proposal to the broader physics community.The core of the nEXO detector is a Time Projection Chamber (TPC), a technology that can identify and suppress with high efficiency most background signals mimicking neutrinoless-double beta decays. The detector will measure the position and energy of each ionizing event occurring inside its volume, as well as finer information about the spatial distribution and sharing of event energy between two detection channels, ionization and scintillation light. Combined with a detector design that minimizes the residual radioactivity in its constituents, this information provides a powerful environment for a neutrino-less double beta decay signal to emerge once all other interactions are properly identified. The UMass Amherst group works on the development of key elements of nEXO. The PI coordinates the design of the nEXO TPC. With his group, he studies novel silicon-based detectors (specifically Silicon PhotoMultipliers, SiPMs) sensitive to the xenon scintillation light (178 nm) that combine good light collection efficiency, minimal radioactive contamination, uniformity of response, and are practically available to cover several square meters of surface in nEXO. An integral part of the program is a continued participation in the EXO-200 experiment, and the analysis of its data. Of particular interest are refined searches for neutrino-less double beta decay of xenon-136 and xenon-134.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

今天科学中的一个基本问题是，为什么宇宙和宇宙中的一切几乎都是由物质组成的，而基本上没有反物质，而描述自然的方程却让我们期待几乎等量的物质和反物质。 该奖项支持位于阿默斯特的马萨诸塞州大学通过研究自然界中最轻的基本粒子中微子是否由物质和反物质组成，对这种不平衡的一种可能起源进行调查。 如果是这样的话，一个非常罕见的核过程称为中微子少双β衰变是可能的。在这种衰变中，一个原子核通过发射两个电子而转变成另一个原子核，这将明确地确定中微子和反中微子是同一种粒子，即它们是马约拉纳粒子。 马萨诸塞大学阿默斯特分校的工作重点是nEXO实验探测器设计的关键研发方面，在实验室与博士后和学生（研究生和本科生）在学术研究密集型环境中进行研究。 PI和他的团队还参与了EXO-200实验的操作和数据分析，EXO-200实验是一个较小规模的nEXO前身，在新墨西哥州运行，是迄今为止对中微子较少的双β衰变最敏感的实验之一。 该奖项支持的活动培训不同背景的人力资源，并开发与美国战略部门相一致的技术，如数据科学和人工智能，核医学和防扩散，以及国家实验室的国家安全计划。马萨诸塞大学阿默斯特粒子天体物理学小组在本科生参与研究方面有着卓越和多样性的记录，阿默斯特基本相互作用中心（ACFI）积极致力于向更广泛的物理学界推广与此提议相关的物理学。nEXO探测器的核心是一个时间投影室（TPC），该技术可以高效地识别和抑制大多数模拟无中微子双β衰变的背景信号。探测器将测量其体积内发生的每个电离事件的位置和能量，以及关于空间分布和两个探测通道（电离光和闪烁光）之间事件能量共享的更精细信息。结合探测器设计，最大限度地减少其成分中的残留放射性，这些信息提供了一个强大的环境，一旦所有其他相互作用被正确识别，就会出现中微子较少的双β衰变信号。马萨诸塞大学阿默斯特分校的研究小组致力于nEXO关键元素的开发。PI负责协调nEXO TPC的设计。与他的团队一起，他研究了对氙闪烁光（178 nm）敏感的新型硅基探测器（特别是硅光电倍增器，SiPM），这些探测器联合收割机良好的光收集效率，最小的放射性污染，响应均匀性，并且实际上可以覆盖nEXO中几平方米的表面。 该计划的一个组成部分是继续参与EXO-200实验及其数据分析。特别令人感兴趣的是对氙-136和氙-134的无中微子双β衰变的精细搜索。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Reflectivity of VUV-sensitive silicon photomultipliers in liquid Xenon

• DOI: 10.1088/1748-0221/16/08/p08002
• 发表时间: 2021-04
• 期刊: Journal of Instrumentation
• 影响因子: 1.3
• 作者: M. Wagenpfeil;T. Ziegler;J. Schneider;A. Fieguth;M. Murra;D. Schulte;L. Althueser;C. Huhmann;C. Weinheimer;T. Michel;G. Anton;G. Adhikari;S. Al Kharusi;E. Angelico;I. Arnquist;I. Badhrees;J. Bane;D. Beck;V. Belov;T. Bhatta;A. Bolotnikov;P. Breur;J. Brodsky;E. Brown;T. Brunner;E. Caden;G. Cao;C. Chambers;B. Chana;S. Charlebois;D. Chernyak;M. Chiu;B. Cleveland;A. Craycraft;T. Daniels;L. Darroch;A. Der Mesrobian-Kabakian;A. De St. Croix;K. Deslandes;R. DeVoe;M. L. di Vacri;M. Dolinski;J. Echevers;M. Elbeltagi;L. Fabris;D. Fairbank;W. Fairbank;J. Farine;S. Ferrara;S. Feyzbakhsh;G. Gallina;P. Gautam;G. Giacomini;C. Gingras;D. Goeldi;A. Gorham;R. Gornea;G. Gratta;E. Hansen;C. Hardy;K. Harouaka;M. Heffner;E. Hoppe;A. House;M. Hughes;A. Iverson;A. Jamil;M. Jewell;A. Karelin;L. Kaufman;R. Krücken;A. Kuchenkov;K.S. Kumar;Y. Lan;A. Larson;K. Leach;D. Leonard;G. Li;S. Li;Z. Li;C. Licciardi;R. Lindsay;R. Maclellan;P. Martel-Dion;N. Massacret;T. McElroy;M. Medina Peregrina;B. Mong;D. Moore;K. Murray;J. Nattress;C. Natzke;R. J. Newby;F. Nolet;O. Nusair;J. Nzobadila Ondze;K. Odgers;A. Odian;J. Orrell;G. S. Ortega;I. Ostrovskiy;C. Overman;S. Parent;A. Piepke;A. Pocar;J. Pratte;E. Raguzin;G. J. Ramonnye;H. Rasiwala;S. Rescia;F. Retière;C. Richard;M. Richman;J. Ringuette;A. Robinson;T. Rossignol;P. Rowson;N. Roy;R. Saldanha;S. Sangiorgio;A. Soma;F. Spadoni;V. Stekhanov;T. Stiegler;M. Tarka;S. Thibado;A. Tidball;J. Todd;T. Totev;S. Triambak;R. Tsang;F. Vachon;V. Veeraraghavan;S. Viel;C. Vivo-Vilches;M. Walent;U. Wichoski;M. Worcester;S.X. Wu;Q. Xia;W. Yan;L. Yang;O. Zeldovich

Event reconstruction in a liquid xenon Time Projection Chamber with an optically-open field cage

• DOI: 10.1016/j.nima.2021.165239
• 发表时间: 2020-09
• 期刊: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
• 作者: T. Stiegler;S. Sangiorgio;J. Brodsky;M. Heffner;S. A. Kharusi;G. Anton;I. Arnquist;I. Badhrees;P. Barbeau;D. Beck;V. Belov;T. Bhatta;A. Bolotnikov;P. Breur;E. Brown;T. Brunner;E. Caden;G. Cao;L. Cao;C. Chambers;B. Chana;S. Charlebois;M. Chiu;B. Cleveland;M. Coon;A. Craycraft;J. Dalmasson;T. Daniels;L. Darroch;A. De St. Croix;A. D. Mesrobian-Kabakian;K. Deslandes;R. DeVoe;M. L. di Vacri;J. Dilling;Y.Y. Ding;M. Dolinski;A. Dragone;J. Echevers;F. Edaltafar;M. Elbeltagi;L. Fabris;D. Fairbank;W. Fairbank;J. Farine;S. Ferrara;S. Feyzbakhsh;G. Gallina;P. Gautam;G. Giacomini;D. Goeldi;R. Gornea;G. Gratta;E. Hansen;E. Hoppe;J. Hössl;A. House;M. Hughes;A. Iverson;A. Jamil;M. Jewell;X.S. Jiang;A. Karelin;L. Kaufman;T. Koffas;R. Krücken;A. Kuchenkov;K.S. Kumar;Y. Lan;A. Larson;K. Leach;B. Lenardo;D. Leonard;G. Li;S. Li;Z. Li;C. Licciardi;P. Lv;R. Maclellan;N. Massacret;T. McElroy;M. Medina-Peregrina;T. Michel;B. Mong;D. Moore;K. Murray;P. Nakarmi;C. Natzke;R. J. Newby;K. Ni;Z. Ning;O. Njoya;F. Nolet;O. Nusair;K. Odgers;A. Odian;M. Oriunno;J. Orrell;G. S. Ortega;I. Ostrovskiy;C. Overman;S. Parent;A. Piepke;A. Pocar;J. Pratte;V. Radeka;E. Raguzin;H. Rasiwala;S. Rescia;F. Retière;M. Richman;A. Robinson;T. Rossignol;P. Rowson;N. Roy;R. Saldanha;K. Skarpaas;A. Soma;G. St-Hilaire;V. Stekhanov;X.L. Sun;M. Tarka;S. Thibado;A. Tidball;J. Todd;T. Totev;R. Tsang;T. Tsang;F. Vachon;V. Veeraraghavan;S. Viel;G. Visser;C. Vivo-Vilches;J. Vuilleumier;M. Wagenpfeil;T. Wager;M. Walent;Q. Wang;W. Wei;L. Wen;U. Wichoski;M. Worcester;S.X. Wu;W.H. Wu;X. Wu;Q. Xia;H. Yang;L. Yang;O. Zeldovich;J. Zhao;Y. Zhou;T. Ziegler

Measurements of electron transport in liquid and gas Xenon using a laser-driven photocathode

• DOI: 10.1016/j.nima.2020.163965
• 发表时间: 2019-11
• 期刊: arXiv: Instrumentation and Detectors
• 作者: O. Njoya;T. Tsang;M. Tarka;W. Fairbank;K. Kumar;Triveni Rao;T. Wager;S. A. Kharusi;G. Anton;I. Arnquist;I. Badhrees;P. Barbeau;D. Beck;V. Belov;T. Bhatta;J. Brodsky;E. Brown;T. Brunner;E. Caden;G. Cao;L. Cao;W. Cen;C. Chambers;B. Chana;S. Charlebois;M. Chiu;B. Cleveland;M. Coon;A. Craycraft;J. Dalmasson;T. Daniels;L. Darroch;S. Daugherty;A. D. S. Croix;A. D. Mesrobian-Kabakian;R. DeVoe;M. Vacri;J. Dilling;Y. Ding;M. Dolinski;A. Dragone;J. Echevers;M. Elbeltagi;L. Fabris;D. Fairbank;J. Farine;S. Ferrara;S. Feyzbakhsh;R. Fontaine;A. Fucarino;G. Gallina;P. Gautam;G. Giacomini;D. Goeldi;R. Gornea;G. Gratta;E. Hansen;M. Heffner;E. Hoppe;J. Hössl;A. House;M. Hughes;A. Iverson;A. Jamil;M. Jewell;X. Jiang;A. Karelin;L. Kaufman;D. Kodroff;T. Koffas;R. Krücken;A. Kuchenkov;Y. Lan;A. Larson;K. Leach;B. Lenardo;D. Leonard;G. Li;S. Li;Z. Li;C. Licciardi;Yuehe Lin;P. Lv;R. Maclellan;T. McElroy;M. Medina-Peregrina;T. Michel;B. Mong;D. Moore;K. Murray;P. Nakarmi;C. Natzke;R. J. Newby;Z. Ning;F. Nolet;O. Nusair;K. Odgers;A. Odian;M. Oriunno;J. Orrell;G. S. Ortega;I. Ostrovskiy;C. Overman;S. Parent;A. Piepke;A. Pocar;J. Pratte;V. Radeka;E. Raguzin;S. Rescia;F. Retière;M. Richman;A. Robinson;T. Rossignol;P. Rowson;N. Roy;J. Runge;R. Saldanha;S. Sangiorgio;K. S. Viii;A. Soma;G. St-Hilaire;V. Stekhanov;T. Stiegler;X. Sun;Jacob Todd;T. Tolba;T. Totev;R. Tsang;F. Vachon;V. Veeraraghavan;S. Viel;G. Visser;C. Vivo-Vilches;J. Vuilleumier;M. Wagenpfeil;M. Walent;Q. Wang;Martin Ward;J. Watkins;M. Weber;W. Wei;L. Wen;U. Wichoski;S. X. Wu;W. Wu;Xiongwei Wu;Q. Xia;H. Yang;Liang Yang;Y. Yen;O. Zeldovich;J. Zhao;Y. Zhou;T. Ziegler

Search for Majoron-emitting modes of Xe136 double beta decay with the complete EXO-200 dataset

使用完整的 EXO-200 数据集搜索 Xe136 双 β 衰变的 Majoron 发射模式

• DOI: 10.1103/physrevd.104.112002
• 发表时间: 2021
• 期刊: Physical Review D
• 影响因子: 5
• 作者: Al Kharusi, S.;Anton, G.;Badhrees, I.;Barbeau, P. S.;Beck, D.;Belov, V.;Bhatta, T.;Breidenbach, M.;Brunner, T.;Cao, G. F.
• 通讯作者: Cao, G. F.

Study of silicon photomultiplier performance in external electric fields

硅光电倍增管在外电场下的性能研究

• DOI: 10.1088/1748-0221/13/09/t09006
• 发表时间: 2018-09-01
• 期刊: JOURNAL OF INSTRUMENTATION
• 影响因子: 1.3
• 作者: Sun, X. L.;Tolba, T.;Ziegler, T.
• 通讯作者: Ziegler, T.