DOCSLIB.ORG

Diurnal Effect of Sub-Gev Dark Matter Boosted by Cosmic Rays

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Diurnal Effect of Sub-Gev Dark Matter Boosted by Cosmic Rays Diurnal Effect of Sub-GeV Dark Matter Boosted by Cosmic Rays Shao-Feng Ge,1,2, ∗ Jianglai Liu,2,1, † Qiang Yuan,3, 4, 5, ‡ and Ning Zhou2, § 1Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China 2School of Physics and Astronomy, Shanghai Jiao Tong University, Key Laboratory for Particle Astrophysics and Cosmology (MOE) & Shanghai Key Laboratory for Particle Physics and Cosmology, Shanghai 200240, China 3Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210033, China 4School of Astronomy and Space Science, University of Science and Technology of China, Hefei 230026, China 5Center for High Energy Physics, Peking University, Beijing 100871, China We point out a new type of diurnal effect for the cosmic ray boosted dark matter (DM). The DM- nucleon interactions not only allow the direct detection of DM with nuclear recoils, but also allow cosmic rays to scatter with and boost the nonrelativistic DM to higher energies. If the DM-nuclei scattering cross sections are sufficiently large, the DM flux is attenuated as it propagates through the Earth, leading to a strong diurnal modulation. This diurnal modulation provides another prominent signature for the direct detection of boosted sub-GeV DM, in addition to signals with higher recoil energy. Introduction – Overwhelming evidence from astrophys- signals in large neutrino experiments [44–46]. ical and cosmological observations supports the existence For sub-GeV DM, the DM-nucleon scattering cross sec- of dark matter (DM) [1], which is gravitationally interact- tion with a contact interaction can be quite sizable, e.g., ing but invisible via electromagnetic interactions. How- as large as 10−31cm2 (see [47] and the references in [35]), ever, the physical nature of DM is poorly understood: in contrast to the light mediator case [48]. With this al- the DM identity is unknown with a possible mass spans lowed interaction strength, DM particles can experience nearly 80 orders of magnitude [2]. The DM direct detec- multiple scatterings and become attenuated when trav- tion [3] aims to verify the existence of DM particles and eling through the Earth [49–52]. If the CRDM flux is measure their interactions via the recoil of target nuclei anisotropic, a diurnal flux modulation at direct detec- or electrons, which is believed to be the most direct way tion experiments is expected [53, 54]. This is different to unveil the nature of DM particles [4, 5]. from the conventional diurnal effect that is mainly for Conventionally, direct detection experiments assume nonrelativistic DM. the existence of nonrelativistic DM confined in the Sub-GeV Dark Matter Boosted by Cosmic Rays – The Galaxy. The gravitational potential of the Galaxy results spatial and spectral distributions of the CRDM flux de- pend on the DM and CR distributions in the Galaxy in an upper limit on the DM velocity of vχ . 600 km/s above which DM can escape [6, 7]. Because of the en- as well as the CRDM scattering processes. Both the DM ergy threshold, which is typically O(keV), the sensitive density and CR intensities vary with their locations in the mass window of direct detection experiments can only Galaxy, becoming more concentrated toward the Galaxy extend down to O(1) GeV via the conventional nuclear center (GC). Therefore, CRs are much more likely to recoil channel. In recent years, to enhance the sensitivity scatter with and boost the DM in the inner Galaxy re- of detecting sub-GeV DM, many approaches have been gion. Even for isotropic scattering, the CRDM flux is highly anisotropic over the sky. arXiv:2005.09480v2 [hep-ph] 9 Mar 2021 explored, including expanding the nuclear recoil detec- tion capability via a low threshold bolometer [8, 9] as Although the CRDM scattering also affects the CRs, well as via the Bremsstrahlung [10] and Migdal [11–17] the effect is important only for a very large scattering −27 2 effects, the direct detection of DM-electron recoils [18– cross section (σχp > 10 cm )[35]. For simplicity, 23], and various novel detection proposals [24–34]. we assume that the CR distribution is unaffected. The CRDM emissivity, which describes its spatial and spec- Another interesting possibility has been recently trum distributions, is given by [36] pointed out: nonrelativistic DM can be boosted by cos- r ∞ r mic rays (CRs) [35, 36] or the solar reflection [37–39]. r ρχ(| |) nCR,i( ,Ti) ζχ( ,Tχ)= dTi max As long as DM has finite interactions with matter, it is mχ T min Tχ (Ti) i=p,He Z i inevitable for the nonrelativistic DM to be scattered and X ×v σ G2(Q2), (1) boosted by the energetic CRs. Although the flux of the i χi i CR-boosted DM (CRDM) is a tiny fraction compared to where Ti and Tχ are the kinetic energies of the CR species min the nonrelativistic DM, it allows explorations of a certain i and the boosted DM with mass mχ, Ti is the mini- parameter space of sub-GeV DM that was previously in- mum CR energy required to boost the DM kinetic energy max accessible [36, 40–43] in direct detection, thus expanding to Tχ, and Tχ is the maximum DM kinetic energy given the sensitive mass region. The CRDM can also produce Ti [36]. There are three main ingredients in Eq. (1): the 2 σ -32 2 -4 GC direction, χp=10 cm 10 ) -1 -7 sr 10 -1 -5 -4 10 -4 -8 halo × 10 mχ=10 GeV 10 (cm s β ) -6 -9 /d 10 -1 10 10-3 GeV Φ )d -10 sr χ 10 -7 ρ -2 / -1 10 10 GeV β s χ 10-11 -2 (m -8 10-4 10-3 10-2 10-1 100 10 β 10-1 GeV (cm -9 χ 10 /dT -10 100 GeV Φ 10 d χ -11 101 GeV T 10 10-12 10-13 10-3 10-2 10-1 100 101 102 103 Tχ (GeV) FIG. 2. The CRDM energy spectra at the GC direction for DM masses 10−4, 10−3, 10−2, 0.1, 1.0, and 10 GeV from top to bottom. The scattering cross section σχp is assumed to be 10−32 cm2. The inset is the distribution of DM velocities, β = v/c, compared to the Maxwellian distribution of the Standard DM Halo. For a clear comparison, we rescale the Standard DM Halo curve by 10−4 (labeled as halo ×10−4 in the inset) so that all curves have a similar height. ing CR spatial distribution, please see the Supplemental Material [67]. FIG. 1. Relative sky maps of CRDM fluxes in the Galactic The DM-nucleus interaction is the least known part in coordinates with amplitude in the GC direction set to unity. Eq. (1). For simplicity, we assume that the DM-nucleus The upper and lower panels are for the NFW and Isothermal cross section σχA has a coherent enhancement, DM density profiles, respectively. m (m + m ) 2 σ = σ A2 A χ p , (2) χA χp m (m + m ) p χ A DM density ρχ(|r|) at location r, the CR density nCR,i times its velocity vi, and the scattering cross section σχi. where σχn = σχp is the constant DM-nucleon cross sec- 2 2 2 2 tion, while m and m are the proton and nuclear masses The form factor Gi(Q ) ≡ 1/(1 + Q /Λi ) [55] is a func- p A tion of the momentum transfer Q with Λp ≈ 770 MeV for the CR. For mχ ≪ mp,mA, the enhancement mainly 2 and ΛHe ≈ 410 MeV [56] for proton and helium, respec- comes from the A factor. Extra enhancement may come 2 2 tively. from (mχ + mp) /mp when mχ goes beyond mp. The dipole hadronic form factor G (Q2) in Eq. (1) suppresses For the DM density ρχ(|r|), we adopt the i nfw the interaction at large momentum transfer Q. Navarro-Frenk-White (NFW) [57] profile, ρχ (r) = 2 The CRDM flux arriving at the Earth along a given ρs/[(r/rs)(1 + r/rs) ] with rs = 20 kpc and −3 direction nˆ is a line-of-sight integral of all contributions ρs = 0.35 GeV cm , as the benchmark DM mass distribution. For comparison, a cored isothermal distri- along the way, iso 2 bution, ρχ (r) = ρs/[1 + (r/rs) ] with rs = 5 kpc and dΦ 1 −3 ˆn r ρ = 1.56 GeV cm , is also studied. These parameters ( ,Tχ)= ζχ( ,Tχ) dl. (3) s dT 4π correspond to a local DM density of 0.4 GeV cm−3 in χ Z our Solar System [58] for both profiles. The difference Fig. 1 shows the relative all-sky maps of the CRDM fluxes between the two profiles and more details are given in in the Galactic coordinate, a spherical coordinate with the Supplemental Material [67]. The amplitudes of the the Sun as its center, the latitude measuring the angle diurnal modulation vary by only around 7% for different above/below the galactic plane, and the longitude mea- density profiles. suring the azimuth angle from the GC. The peak value at For the CR contribution in Eq. (1), we employ the the GC is set to 1. The top (bottom) panel presents the GALPROP [59] code (version 54) to simulate its distri- NFW (isothermal) profile. The CRDM fluxes are clearly bution. In this Letter, we only consider the dominating anisotropic, with the maximum (the GC direction) and proton and helium species of CRs, and leave the rest, in the minimum differing by about two orders of magnitude. particular electrons and positrons, for future discussions.
Load more

Recommended publications
  • Future Plan of the Pandax Experiment
    Future plan of the PandaX Experiment - report at the CJPL International Advisory Committee meeting PandaX Collaboration, 9 Nov., 2016 The PandaX (Particle and astrophysical Xenon) observatory uses xenon as target and detector to search for WIMP particles as well as neutrinoless double beta decay (NLDBD) in 136Xe. At present, the PandaX-II experiment is in operation in CJPL-I. The future PandaX program will pursue the following three main directions: 1. Continue the operation of PandaX-II until a total of 2-year exposure; 2. Develop and operate a multi-ton multi-purpose liquid xenon experiment, PandaX-xT, to push further the dark matter search; 3. Develop and operate a 200-kg (upgradable to ton-scale) high pressure gas TPC (HpgTPC), PandaX-III, to search for NLDBD in 136Xe. Each direction is elaborated below. PandaX-II operation PandaX-II has published the world leading WIMP limit with a 99-day exposure, reaching an upper limit to spin-independent WIMP-nucleon cross section of 2.5x10-46cm2 [1]. The current plan is to maintain stable operation until we have data with a 2-year total live time. Calibration runs will be interleaved to monitor the detector response. The wealth of low background data will allow us to pursue many different physics analyses (in additional to the standard WIMP- nucleon elastic scattering), including constraints to generic WIMP-nucleon operators, light WIMPs, inelastic WIMPs, limits to solar and galactic axions, etc. We will also use the PandaX-II detector to test new technologies for a future multi-ton detector, e.g. online Kr removal, upgrade of the trigger/electronics system to achieve a lower threshold and a higher data bandwidth, alternative electron recoil and nuclear recoil calibrations, etc.
    [Show full text]
  • Gustavo Marques-Tavares, Stanford Institute for Theoretical Physics
    Detecting dark particles from Supernovae Gustavo Marques-Tavares, Stanford Institute for Theoretical Physics In collaboration with W. deRocco, P. Graham, D. Kasen and S. Rajendran Dark matter WIMP searches 5 -37 ACKNOWLEDGMENTS 10 -38 10 PandaX-II 2016 10-39 LUX 2016 ) 2 10-40 CDMSLite 2015 CRESST-II 2015 10-41 10-42 -43 10 SuperCDMS Post LHC1 mSUSY constraint 1700 kg-days 10-44 10-45 -46 10 6 t-y PandaX-4T 10-47 XENON1T 2 t-y LZ 15.6 t-y SI WIMP-nucleon cross section (cm XENONnT 20 t-y 10-48 200 t-y xenon (DARWIN or PandaX-30T) 10-49 Neutrino coherent scattering 10-50 1 10 102 103 WIMP mass (GeV/c2) *Figure taken from arxiv:1709.00688 This work is supported by grants from the Na- FIG. 4. The projected sensitivity (dashed curves) on the spin- tional Science Foundation of China (Nos. 11435008, independent WIMP-nucleon cross-sections of a selected num- ber of upcoming and planned direct detection experiments, 11455001, 11505112 and 11525522), a grant from the including XENON1T [34], PandaX-4T, XENONnT [34], Ministry of Science and Technology of China (Grant No. LZ [35], DARWIN [36] or PandaX-30T, and SuperCDMS [56]. 2016YFA0400301), and in part by the Chinese Academy Currently leading limits in Fig. 1 (see legend), the neutrino of Sciences Center for Excellence in Particle Physics ‘floor’ [20], and the post-LHC-Run1 minimal-SUSY allowed (CCEPP), the Key Laboratory for Particle Physics, As- contours [21] are overlaid in solid curves for comparison. The trophysics and Cosmology, Ministry of Education, and di↵erent crossings of the experimental sensitivities and the Shanghai Key Laboratory for Particle Physics and Cos- 2 neutrino floor at around a few GeV/c are primarily due to mology (SKLPPC).
    [Show full text]
  • Neutrinoless Double Beta Decay Searches
    FLASY2019: 8th Workshop on Flavor Symmetries and Consequences in 2016 Symmetry Magazine Accelerators and Cosmology Neutrinoless Double Beta Decay Ke Han (韩柯) Shanghai Jiao Tong University Searches: Status and Prospects 07/18, 2019 Outline .General considerations for NLDBD experiments .Current status and plans for NLDBD searches worldwide .Opportunities at CJPL-II NLDBD proposals in China PandaX series experiments for NLDBD of 136Xe 07/22/19 KE HAN (SJTU), FLASY2019 2 Majorana neutrino and NLDBD From Physics World 1935, Goeppert-Mayer 1937, Majorana 1939, Furry Two-Neutrino double beta decay Majorana Neutrino Neutrinoless double beta decay NLDBD 1930, Pauli 1933, Fermi + 2 + (2 ) Idea of neutrino Beta decay theory 136 136 − 07/22/19 54 → KE56 HAN (SJTU), FLASY2019 3 ̅ NLDBD probes the nature of neutrinos . Majorana or Dirac . Lepton number violation . Measures effective Majorana mass: relate 0νββ to the neutrino oscillation physics Normal Inverted Phase space factor Current Experiments Nuclear matrix element Effective Majorana neutrino mass: 07/22/19 KE HAN (SJTU), FLASY2019 4 Detection of double beta decay . Examples: . Measure energies of emitted electrons + 2 + (2 ) . Electron tracks are a huge plus 136 136 − 54 → 56 + 2 + (2)̅ . Daughter nuclei identification 130 130 − 52 → 54 ̅ 2νββ 0νββ T-REX: arXiv:1512.07926 Sum of two electrons energy Simulated track of 0νββ in high pressure Xe 07/22/19 KE HAN (SJTU), FLASY2019 5 Impressive experimental progress . ~100 kg of isotopes . ~100-person collaborations . Deep underground . Shielding + clean detector 1E+27 1E+25 1E+23 1E+21 life limit (year) life - 1E+19 half 1E+17 Sn Ca νββ Ge Te 0 1E+15 Xe 1E+13 1940 1950 1960 1970 1980 1990 2000 2010 2020 Year .
    [Show full text]
  • 27. Dark Matter
    1 27. Dark Matter 27. Dark Matter Written August 2019 by L. Baudis (Zurich U.) and S. Profumo (UC Santa Cruz). 27.1 The case for dark matter Modern cosmological models invariably include an electromagnetically close-to-neutral, non- baryonic matter species with negligible velocity from the standpoint of structure formation, gener- ically referred to as “cold dark matter” (CDM; see The Big-Bang Cosmology—Sec. 22 of this Re- view). For the benchmark ΛCDM cosmology adopted in the Cosmological Parameters—Sec. 25.1 of this Review, the DM accounts for 26.4% of the critical density in the universe, or 84.4% of the total matter density. The nature of only a small fraction, between at least 0.5% (given neutrino os- cillations) and at most 1.6% (from combined cosmological constraints), of the non-baryonic matter content of the universe is known: the three Standard Model neutrinos (see the Neutrino Masses, Mixing, and Oscillations—Sec. 14 of this Review) ). The fundamental makeup of the large majority of the DM is, as of yet, unknown. Assuming the validity of General Relativity, DM is observed to be ubiquitous in gravitation- ally collapsed structures of size ranging from the smallest known galaxies [1] to galaxies of size comparable to the Milky Way [2], to groups and clusters of galaxies [3]. The mass-to-light ratio is observed to saturate at the largest collapsed scales to a value indicative, and close to, what inferred from other cosmological observations for the universe as a whole [4]. In such collapsed structures, the existence of DM is inferred directly using tracers of mass enclosed within a certain radius such as stellar velocity dispersion, rotation curves in axisymmetric systems, the virial theorem, gravitational lensing, and measures of the amount of non-dark, i.e.
    [Show full text]
  • 35. Particle Detectors for Non-Accelerator Physics
    1 35. Particle Detectors for Non-Accelerator Physics 35. Particle Detectors for Non-Accelerator Physics 35.1 Introduction . 1 35.2 High-energy cosmic-ray hadron and gamma-ray detectors . 2 35.2.1 Atmospheric fluorescence detectors . 2 35.2.2 Atmospheric Cherenkov telescopes for high-energy gamma ray astronomy . 5 35.3 Large neutrino detectors . 8 35.3.1 Deep liquid detectors for rare processes . 8 35.3.2 Neutrino telescopes . 12 35.3.3 Radio emission from (ultra-)high energy particle showers . 20 35.4 Large time-projection chambers for rare event detection . 27 35.4.1 Dark matter and other low energy signals . 28 35.4.2 0νββ Decay . 31 35.5 Sub-Kelvin detectors . 32 35.5.1 Equilibrium thermal detectors . 32 35.5.2 Nonequilibrium Detectors . 34 35.6 Low-radioactivity background techniques . 36 35.6.1 Defining the problem . 37 35.6.2 Environmental radioactivity . 37 35.6.3 Radioactive impurities in detector and shielding components . 39 35.6.4 Radon and its progeny . 40 35.6.5 Cosmic rays . 41 35.6.6 Neutrons . 42 35.1 Introduction Non-accelerator experiments have become increasingly important in particle physics. These include cosmic ray experiments (with surface, space and underground detectors), neutrino oscilla- tion measurements with solar and atmospheric neutrinos in underground laboratories, searches for neutrino-less double beta decays and dark matter candidates again in underground laboratories, and searches for more exotic phenomena. The detectors are in the majority of the cases differ- ent from those used at accelerators. Even when the detectors are based on the same physics (e.
    [Show full text]
  • An Improved Design of the Readout Base Board of the Photomultiplier Tube for Future Pandax Dark Matter Experiments
    Prepared for submission to JINST An improved design of the readout base board of the photomultiplier tube for future PandaX dark matter experiments Qibin Zheng,0,2 Yanlin Huang,0 Di Huang,1 Jianglai Liu,1,3 Xiangxiang Ren,4 Anqing Wang,4 Meng Wang,4 Jijun Yang,1 Binbin Yan,1 Yong Yang1 0Institute of Biomedical Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China 1INPAC, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai Laboratory for Particle Physics and Cosmology, Shanghai 200240, China 2Terahertz Technology Innovation Research Institute, University of Shanghai for Science and Technology, Shanghai 200093, China 3Tsung-Dao Lee Institute, Shanghai Jiaotong University, Shanghai, 200240, China 4School of Physics and Key Laboratory of Particle Physics and ParticleIrradiation (MOE), Shandong University, Jinan 250100, China E-mail: [email protected] Abstract: The PandaX project consists of a series of xenon-based experiments that are used to search for dark matter (DM) particles and to study the fundamental properties of neutrinos. The next DM experiment PandaX-4T will be using 4 ton liquid xenon in the sensitive volume, which is nearly a factor of seven larger than that of the previous experiment PandaX-II. Due to the increasing target mass, the sensitivity of searching for both DM and neutrinoless double-beta decay (0aVV) signals in the same detector will be significantly improved. However, the typical energy of interest for 0aVV signals is at the MeV scale, which is much higher than that of most popular DM signals. In the baseline readout scheme of the photomultiplier tubes (PMTs), the dynamic range is very limited.
    [Show full text]
  • Search for Neutrinos from Decaying Dark Matter with Icecube
    Search for neutrinos from decaying dark matter with IceCube The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation Aartsen, M. G. et al. "Search for neutrinos from decaying dark matter with IceCube." European Physical Journal C: Particles and Fields 78 (October 2018): 831 © 2018 The Author(s) As Published https://doi.org/10.1140/epjc/s10052-018-6273-3 Publisher Springer Berlin Heidelberg Version Final published version Citable link http://hdl.handle.net/1721.1/118985 Terms of Use Creative Commons Attribution Detailed Terms http://creativecommons.org/licenses/by/4.0/ Eur. Phys. J. C (2018) 78:831 https://doi.org/10.1140/epjc/s10052-018-6273-3 Regular Article - Experimental Physics Search for neutrinos from decaying dark matter with IceCube IceCube Collaborationa , M. G. Aartsen16, M. Ackermann51, J. Adams16,J.A.Aguilar12, M. Ahlers20, M. Ahrens43, I. Al Samarai25, D. Altmann24, K. Andeen33, T. Anderson48, I. Ansseau12, G. Anton24, C. Argüelles14, J. Auffenberg1, S. Axani14, P. Backes1, H. Bagherpour16,X.Bai40, J. P. Barron23, S. W. Barwick27, V. Baum32, R. Bay8, J. J. Beatty18,19, J. Becker Tjus11, K.-H. Becker50, S. BenZvi42, D. Berley17, E. Bernardini51, D. Z. Besson28, G. Binder8,9, D. Bindig50, E. Blaufuss17,S.Blot51, C. Bohm43, M. Börner21,F.Bos11, S. Böser32, O. Botner49, E. Bourbeau20, J. Bourbeau31, F. Bradascio51, J. Braun31, M. Brenzke1,H.-P.Bretz51,S.Bron25, J. Brostean-Kaiser51, A. Burgman49,R.S.Busse31, T. Carver25, E. Cheung17, D. Chirkin31, A. Christov25, K. Clark29, L. Classen35, G. H. Collin14, J.
    [Show full text]
  • Arxiv:2008.10279V2 [Hep-Ph] 4 Jun 2021
    Constraints on General Light Mediators from PandaX-II Electron Recoil Data Amir N. Khan1, ∗ 1Max-Planck-Institut f¨urKernphysik, Postfach 103980, D-69029 Heidelberg, Germany (Dated: June 7, 2021) PandaX-II has analyzed their complete data set of the electron recoil energy spectrum and has confirmed the XENON1T (1-7) keV excess, although the excess was also found compatible with the total background. Treating the background as well known, in which case it provides a good fit to the observed spectrum, one can expect stronger constraints on any new physics model with this data. With this motivation, we derive constraints on the new general vector (V), axial-vector (A), scalar (S) and pseudoscalar (P) interactions if any of them contribute to the neutrino-electron elastic −7 scattering. The derived constraints on the couplings at 90% C.L., respectively, are gV 0 . 32 × 10 −7 −7 for the mediator mass . 10 keV, gA0 . 34 × 10 for mass . 10 keV, gS . 49 × 10 for mass . 20 −7 keV and gP . 67 × 10 for mass . 30 keV. I. INTRODUCTION those from ref. [8] and other experiments. To be more specific, here we will investigate the possibility of general Recently, PandaX-II has observed an excess in the elec- neutrino nonstandard interactions that could modify the tron recoil energy spectrum [1] following a similar obser- neutrino-electron elastic scattering at the low energy end vation by XENON1T [2]. The expected background lies of the observed energy spectrum. within 1σ of the experimental error in the (1−7) keV re- Treating the background reported by PandaX-II as coil energy region.
    [Show full text]
  • Potential Isotope Needs of Double Beta Decay and Dark Matter Experiments
    Potential Isotope Needs of Double Beta Decay and Dark Matter Experiments Allena K Opper & James Whitmore Issues for NLDBD Experiments Issues for Dark Matter Experiments Isotope Needs Double Beta decay M.Goeppert-Mayer, Phys. Rev. 48 (1935) 512 Can only occur for a Majorana neutrino! Atomic number (Z) Some candidate nuclei: 76Ge, 82Se, 100Mo, 130Te, 136Xe Fifth Workshop on Isotope Federal Supply and Demand 2 RECOMMENDATION II: “The excess of matter over antimatter in the universe is one of the most compelling mysteries in all of science. The observation of neutrinoless double beta decay in nuclei would immediately demonstrate that neutrinos are their own antiparticles and would have profound implications for our understanding of the matter-antimatter mystery. “We recommend the timely development and deployment of a U.S.-led ton-scale neutrinoless double beta decay experiment.” INITIATIVE B: “We recommend vigorous detector and accelerator R&D in support of the neutrinoless double beta decay program and the EIC.” Fifth Workshop on Isotope Federal Supply and Demand 3 Neutrinoless Double Beta Decay •Large exposure 2nbb spectrum 0nbb peak (5% FWHM) (normalized to 1) (normalized to 10-6) •High isotopic abundance •Good energy resolution •Low background •High detection efficiency 0nbb peak (5% FWHM) (normalized to 10-2) Fifth Workshop on Isotope Federal Supply and Demand 4 Isotope choice 2 -1 æ 2 ö 2 g m = çT 0nbb G0nbb E , Z M 0nbb - V M 0nbb ÷ bb ç 1/2 ( 0 ) GT 2 F ÷ è gA ø (light Majorana neutrino exchange mechanism only) R.G.H. Robertson, Mod. Phys. Lett. A 28, 1350021 (2013).
    [Show full text]
  • Searching for Solar Axions Using Data from the Sudbury Neutrino Observatory
    PHYSICAL REVIEW LETTERS 126, 091601 (2021) Searching for Solar Axions Using Data from the Sudbury Neutrino Observatory Aagaman Bhusal ,1,2 Nick Houston ,3,* and Tianjun Li1,2 1CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China 2School of Physical Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China 3Institute of Theoretical Physics, Faculty of Science, Beijing University of Technology, Beijing 100124, China (Received 20 April 2020; accepted 1 February 2021; published 2 March 2021) We explore a novel detection possibility for solar axions, which relies only on their couplings to nucleons, via the axion-induced dissociation of deuterons into their constituent neutrons and protons. An opportune target for this process is the now-concluded Sudbury Neutrino Observatory (SNO) experiment, which relied upon large quantities of heavy water to resolve the solar neutrino problem. From the full SNO 3 ≡ 1 − dataset we exclude in a model-independent fashion isovector axion-nucleon couplings jgaNj 2 jgan −5 −1 gapj > 2 × 10 GeV at 95% C.L. for sub-MeV axion masses, covering previously unexplored regions of the axion parameter space. In the absence of a precise cancellation between gan and gap this result also exceeds comparable constraints from other laboratory experiments, and excludes regions of the parameter space for which astrophysical constraints from SN1987A and neutron star cooling are inapplicable due to axion trapping. DOI: 10.1103/PhysRevLett.126.091601 Introduction.—Arising straightforwardly as a minimal experimental convenience, most of the existing axion extension of the standard model, and in particular the literature rests similarly on axion-photon interactions.
    [Show full text]
  • Search for Light Dark Matter–Electron Scattering in the Pandax-II Experiment
    PHYSICAL REVIEW LETTERS 126, 211803 (2021) Search for Light Dark Matter–Electron Scattering in the PandaX-II Experiment Chen Cheng,2 Pengwei Xie,3 Abdusalam Abdukerim,1 Wei Chen,1 Xun Chen,1,4 Yunhua Chen,5 Xiangyi Cui,3 Yingjie Fan,6 Deqing Fang,7 Changbo Fu,7 Mengting Fu,8 Lisheng Geng,9,10 Karl Giboni,1 Linhui Gu,1 Xuyuan Guo,5 Ke Han,1 Changda He,1 Shengming He,5 Di Huang,1 Yan Huang,5 Yanlin Huang,11 † Zhou Huang,1 Xiangdong Ji,12 Yonglin Ju,13 Shuaijie Li,3 Qing Lin,14,15 Huaxuan Liu,13 Jianglai Liu,1,3,4, Liqiang Liu,5 Xiaoying Lu,16,17 Wenbo Ma,1 Yugang Ma,7 Yajun Mao,8 Yue Meng ,1,4,* Parinya Namwongsa,1 Kaixiang Ni,1 Jinhua Ning,5 Xuyang Ning,1 Xiangxiang Ren,16,17 Nasir Shaheed,16,17 Changsong Shang,5 Guofang Shen,9 Lin Si,1 Andi Tan,12 Anqing Wang,16,17 Hongwei Wang,18 Meng Wang,16,17 Qiuhong Wang,7 Siguang Wang,8 Wei Wang,2 Xiuli Wang,13 Zhou Wang,1,4 Mengmeng Wu,2 Shiyong Wu,5 Weihao Wu,1 Jingkai Xia,1 Mengjiao Xiao,12 Xiang Xiao,2 Binbin Yan,1 Jijun Yang,1 Yong Yang,1 Chunxu Yu,6 Jumin Yuan,16,17 Ying Yuan,1 Xinning Zeng,1 Dan Zhang,12 Tao Zhang,1 Li Zhao,1 Qibin Zheng,11 Jifang Zhou,5 Ning Zhou,1 and Xiaopeng Zhou9 (PandaX-II Collaboration) 1School of Physics and Astronomy, Shanghai Jiao Tong University, Key Laboratory for Particle Astrophysics and Cosmology (MOE), Shanghai Key Laboratory for Particle Physics and Cosmology, Shanghai 200240, China 2School of Physics, Sun Yat-Sen University, Guangzhou 510275, China 3Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China 4Shanghai Jiao Tong University
    [Show full text]
  • Recent Pandax-II Results on Dark Matter Search and Status of Pandax-4T
    Recent PandaX-II Results on Dark Matter Search and Status of PandaX-4T Yong Yang Shanghai Jiao Tong University On behalf of Collaboration 12th IDM conference, Brown University 2018/7/24 Yong Yang, SJTU 1 Outline • Introduction to PandaX experiment and China Jinping Underground Laboratory • Recent results from PandaX-II • PandaX Future 2018/7/24 Yong Yang, SJTU 2 PandaX Collaboration Shanghai Jiao Tong University Formed in 2009, ~50 people Peking University Shandong University Nankai University Shanghai Institute of Applied Physics Yalong Hydropower Company University of Maryland University of Science & Technology of China China Institute of Atomic Energy Sun Yat-Sen University Lawrence Berkeley National Lab Alternative Energies & Atomic Energy Commission University of Zaragoza Suranaree University of Technology 2018/7/24 Yong Yang, SJTU 3 China JingPing Underground Lab • Deepest (6800 m.w.e ), 1µ/week/m2 • Horizontal access! Jinping Mountain 2400m 8000m 2018/7/24 Yong Yang, SJTU 4 PandaX experiments PandaX = Particle and Astrophysical Xenon Experiments PandaX-III: Phase I: Phase II: PandaX-xT: 200 kg to 1 ton 120 kg DM 500 kg DM multi-ton DM 136Xe 0vDBD 2009-2014 2014-2017 future future 2018/7/24 Yong Yang, SJTU 5 PandaX-II dual-phase TPC • 60 cm x 60 cm dual-phase xenon Time Projection Chamber • Measure bothD ascintillationrk matte (S1)r se andarc delayedhes w ichargeth du (S2)al-p signalhase TPC • 3-D vertexing • Excellent background rejection Drift time S1 S2 Drift time S1 S2 S1 S2 Dark matter: nuclear recoil (NR) Gamma background: electron recoil (ER) 2018/7/24 Yong Yang, SJTU 6 (S2/S1)NR<<(S2/S1)ER 5 Assembling the detector 2018/7/24 Yong Yang, SJTU 7 PandaX-II Site 2018/7/24 Yong Yang, SJTU 8 PandaX-II Run History Released Run9 =79.6 days, exposure: 26.2 ton-day DM Data Run10 = 77.1 days, exposure: 27.9 ton-day Mar.
    [Show full text]