The highly radiopure ≃ 250 kg NaI(Tl) DAMA/LIBRA set-up is running at the Gran Sasso National Laboratory of the INFN. In this paper the first result obtained by exploiting the model independent ...annual modulation signature for Dark Matter (DM) particles is presented. It refers to an exposure of 0.53 ton×yr. The collected DAMA/LIBRA data satisfy all the many peculiarities of the DM annual modulation signature. Neither systematic effects nor side reactions able to account for the observed modulation amplitude and to contemporaneously satisfy all the several requirements of this DM signature are available. Considering the former DAMA/NaI and the present DAMA/LIBRA data all together (total exposure 0.82 ton×yr), the presence of Dark Matter particles in the galactic halo is supported, on the basis of the DM annual modulation signature, at 8.2
σ
C.L.; in particular, in the energy interval (2–6) keV, the modulation amplitude is (0.0131±0.0016) cpd/kg/keV and the phase and the period are well compatible with June 2
nd
and one year, respectively.
New results from DAMA/LIBRA Bernabei, R.; Belli, P.; Cappella, F. ...
The European physical journal. C, Particles and fields,
05/2010, Letnik:
67, Številka:
1-2
Journal Article
Recenzirano
Odprti dostop
DAMA/LIBRA is running at the Gran Sasso National Laboratory of the I.N.F.N. Here the results obtained with a further exposure of 0.34 ton × yr are presented. They refer to two further annual cycles ...collected one before and one after the first DAMA/LIBRA upgrade occurred on September/October 2008. The cumulative exposure with those previously released by the former DAMA/NaI and by DAMA/LIBRA is now 1.17 ton × yr, corresponding to 13 annual cycles. The data further confirm the previous positive results obtained investigating the presence of Dark Matter (DM) particles in the galactic halo by means of the model independent Dark Matter annual modulation signature; the confidence level is now 8.9
σ
for the cumulative exposure. In particular, with the cumulative exposure the modulation amplitude of the
single-hit
events in the (2–6) keV energy interval measured in NaI(Tl) target is (0.0116±0.0013) cpd/kg/keV; the measured phase is (146±7) days and the measured period is (0.999±0.002) yr, values well in agreement with those expected for the DM particles.
TeV dark matter in the disk Nozzoli, F.
Astroparticle physics,
11/2011, Letnik:
35, Številka:
4
Journal Article
Recenzirano
Odprti dostop
► The data collected by different direct detection experiments are reanalyzed. ► The case of a rotating halo is considered. ► Dark matter particles with mass in the TeV scale are compatible with the ...experimental data.
DAMA and CoGeNT annual modulation data and, CDMS-II, EDELWEISS-II, CRESST excesses of events over the expected background are reanalyzed in terms of a dark matter particle signal considering the case of a rotating halo. It is found that the configurations of very high mass dark matter particles in a corotating cold flux are favored by data. A similar high-mass/low-velocity solution could be of interest in the light of the positron/electron excess measured by PAMELA and Fermi LAT in cosmic rays.
The precise measurement of cosmic-ray antinuclei serves as an important means for identifying the nature of dark matter and other new astrophysical phenomena, and could be used with other cosmic-ray ...species to understand cosmic-ray production and propagation in the Galaxy. For instance, low-energy antideuterons would provide a “smoking gun” signature of dark matter annihilation or decay, essentially free of astrophysical background. Studies in recent years have emphasized that models for cosmic-ray antideuterons must be considered together with the abundant cosmic antiprotons and any potential observation of antihelium. Therefore, a second dedicated Antideuteron Workshop was organized at UCLA in March 2019, bringing together a community of theorists and experimentalists to review the status of current observations of cosmic-ray antinuclei, the theoretical work towards understanding these signatures, and the potential of upcoming measurements to illuminate ongoing controversies. This review aims to synthesize this recent work and present implications for the upcoming decade of antinuclei observations and searches. This includes discussion of a possible dark matter signature in the AMS-02 antiproton spectrum, the most recent limits from BESS Polar-II on the cosmic antideuteron flux, and reports of candidate antihelium events by AMS-02; recent collider and cosmic-ray measurements relevant for antinuclei production models; the state of cosmic-ray transport models in light of AMS-02 and Voyager data; and the prospects for upcoming experiments, such as GAPS. This provides a roadmap for progress on cosmic antinuclei signatures of dark matter in the coming years.
Abstract
Time-dependent energy spectra of galactic cosmic rays (GCRs) carry crucial information regarding their origin and propagation throughout the interstellar environment. When observed at the ...Earth, after traversing the interplanetary medium, such spectra are heavily affected by the solar wind and the embedded solar magnetic field permeating the inner sectors of the heliosphere. The activity of the Sun changes significantly over an 11 yr solar cycle—and so does the effect on cosmic particles; this translates into a phenomenon called solar modulation. Moreover, GCR spectra during different epochs of solar activity provide invaluable information for a complete understanding of the plethora of mechanisms taking place in various layers of the Sun’s atmosphere and how they evolve over time. The High-Energy Particle Detector (HEPD-01) has been continuously collecting data since 2018 August, during the quiet phase between solar cycles 24 and 25; the activity of the Sun is slowly but steadily rising and is expected to peak around 2025/2026. In this paper, we present the first spectra for ∼50–250 MeV galactic protons measured by the HEPD-01 instrument—placed on board the CSES-01 satellite—from 2018 August to 2022 March over a one-Carrington-rotation time basis. Such data are compared to the ones from other spaceborne experiments, present (e.g., EPHIN, Parker Solar Probe) and past (PAMELA), and to a state-of-the-art three-dimensional model describing the GCRs propagation through the heliosphere.
The channeling effect of low energy ions along the crystallographic axes and planes of NaI(Tl) crystals is discussed in the framework of corollary investigations on WIMP dark matter candidates. In ...fact, the modeling of this existing effect implies a more complex evaluation of the luminosity yield for low energy recoiling Na and I ions. In the present paper related phenomenological arguments are developed and possible implications are discussed at some extent.
The observation of sub-GeV antideuteron in the cosmic ray flux, could be a very strong signature of dark matter annihilation in our galaxy. Goal of the Anti Deuteron Helium Detector (ADHD) project is ...to study the signatures offered by an high pressure Helium target for the identification of antideuterons in space.
The observation of sub-GeV antideuteron in the cosmic ray flux could be a very strong signature of dark matter (DM) annihilation in our galaxy. The predicted antideuteron flux resulting from ...secondary interactions of primary cosmic rays with the Inter-Stellar medium is expected to be very low and in particular is kinematically suppressed at low energy (sub-GeV). Well motivated theories beyond the Standard Model contain viable dark matter candidates, which could lead to a significant enhancement of the antideuteron flux due to annihilation or decay of dark matter particles. This flux contribution is believed to be relatively large at low energies, where the secondary background is suppressed, which leads to an high interest in the development of new detection techniques for low energy antideuteron. Current search of antideuteron in cosmic rays are based on the well established technique of magnetic spectrometry (BESS-Polar II and AMS-02 experiments). With the aim to explore kinetic energy regions below 0.2 GeV/n, i.e. below the lower threshold of current and past magnetic spectrometers, some new detection techniques, involving stopping antideuterons captured to form exotic atoms, have been developed. The GAPS experiment, based on the detection of characteristics X-rays, and the ADHD concept, based on the metastable states in Helium target, will be described. In particular the performances of an high pressure (200 bar) Helium scintillator prototype, capable of fast timing and good spatial and energy resolution will be shown. As a result of the preliminary test phase of this prototype in the INFN-TIFPA laboratory, the perspectives of this detection technique for antiproton rejection and its sensitivity to the Dark Matter search in the antideuteron annihilation channel will be described.
The deuteron flux in cosmic rays is one of the most valuable tools for understanding the propagation of CR in the galaxy and constrain the models that describe it. In this work, a new preliminary ...measurement of D flux is presented, obtained from the data of the AMS-02 experiment.
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