The SIMPLE Collaboration has reported results from their superheated C2ClF5 droplet detectors, including a description of acoustic discrimination between αdecays and nuclear recoils. Our concern is that the events in the neutron calibration data and the events identified as neutrons in the physics data are not drawn from the same parent distribution. This fact calls into question the identification of the background events as neutrons, the use of the calibration data to define the acceptance of WIMP-induced nuclear recoils, and the observation of discrimination against α's.
Comment on the paper "On the correlation between the local dark matter and stellar velocities"
我们简要评论了“关于局部暗物质和恒星速度之间的相关性”（Bozorgnia et al. 2018），该论文旨在测试我们之前关于恒星和暗物质运动学相关性的主张（Herzog-Arbeitman et al. 2017; Necib et al. 2018）。Bozorgnia等人（2018）没有准确地提出这些论文的结论，因此我们在这里澄清它们。
We reply to the criticisms moved in [1] against our results presented in [2]. In particular, we show that our fractal model has none of the problems claimed in [1]. The latters can be addressed to the overlooked nonlinear behaviour of the Einstein's equations.
Comment on "Is Dark Matter with Long-Range Interactions a Solution to All Small-Scale Problems of ΛCDM Cosmology?"
In Phys. Rev. Lett. 109（2012）231301，van den Aarssen等人试图通过引入暗物质粒子和MeV质量矢量玻色子之间的相互作用来解决冷暗物质场景中的所有小尺度结构问题。此外，后者与普通中微子耦合，为此需要中微子-矢量玻色子耦合常数10^{-5} < g_nu < 0.1。我们表明，这种暗物质的情况下，受到大爆炸核合成的限制性约束。
An unidentified line at energy around 3.5 keV was detected in the spectra of dark matter-dominated objects. Recent work of Dessert et al. [1812.06976] used 30 Msec of XMM-Newton blank-sky observations to constrain the admissible line flux, challenging its dark matter decay origin. We demonstrate that these bounds are overestimated by more than an order of magnitude due to improper background modeling. Therefore the dark matter interpretation of the 3.5 keV signal remains viable.
Bramante, Delgado, and Martin [Phys. Rev. D96, 063002(2017)., hereafter BDM17] extended the analytical formalism of dark matter (DM) capture in a very important way, which allows, in principle, the use of compact astrophysical objects, such as neutron stars (NS), as dark matter detectors. In this comment, we point out the existence of a region in the dark matter neutron scattering cross section $(σ_{nX})$ vs. dark matter mass $(m_{X})$ where the constraining power of this method is lost. This corresponds to a maximal temperature ($T_{crit}$) the NS has to have, in order to serve as a dark matt…
A comment on power-law inflation with a dark radiation component
Tram et al. 2016最近指出，存在暗辐射成分的幂律暴胀可以缓解Riess et al.（2016）确定的哈勃常数局部值与普朗克合作从CMB各向异性数据导出的值之间存在于标准LCDM中的3.3 sigma张力。在这篇评论中，我们简单地指出，这个有趣的建议无助于解决普朗克数据和，例如，弱透镜效应测量此外，当从普朗克HFI数据获得的再电离光学深度的最新约束包括在分析中时，$H_0$张力重新出现，这种情况失去了吸引力。
Inspired by our recent paper "reshuffled SIMP dark matter", we notice that the reaction rate of the two-loop induced $2 \to 2$ process may dominate over or be comparable with that of the $3 \to 2$ process at the chemical freezeout of Co-SIMP dark matter [Phys. Rev. Lett. 125, 131301 (2020)], especially when the Co-SIMP mass is close to the standard model particle mass (called the edge case). To check our point, we then derive the Boltzmann equation with all relevant annihilation cross sections in an electrophilic model and numerically solve it to obtain the cosmological evolution of Co-SIMP da…
The dark matter explanation of the 3.5 keV line is strongly disfavored by our work in Dessert et al. 2020. Boyarsky et al. 2020 questions that conclusion: modeling additional background lines is claimed to weaken the limit sufficiently to re-allow a dark matter interpretation. We respond as follows. 1) A more conservative limit is obtained by modeling additional lines; this point appeared in its entirety in our work in Dessert et al., though we also showed that the inclusion of such lines is not necessary. 2) Despite suggestions in Boyarsky et al., even the more conservative limits strongly di…
Numerical Evidence for Dark Star Formation: A Comment on "Weakly Interacting Massive Particle Dark Matter and First Stars: Suppression of Fragmentation in Primordial Star Formation" by Smith et al. 2012, ApJ 761, 154
Comment on the paper "Dark matter searches going bananas: the contribution of Potassium (and Chlorine) to the 3.5 keV line" by T. Jeltema and S. Profumo
Dark matter is one of the biggest open questions in physics today. It is known that it interacts gravitationally with luminous matter, so accelerometer-based searches are inherently interesting. In this article we present recent (and future) searches for dark matter candidates such as feebly interacting matter trapped inside the Earth, scalar-matter domain walls and axion quark nuggets, with accelerometer networks and give an outlook of how new atomic-interferometry-based accelerometer networks could support dark matter searches.
