Fri·Jan 28, 2022Friday·January 28, 2022

1. 01*

   Taming modeling uncertainties with Mass Unspecific Supervised Tagging

   J. A. Aguilar-Saavedra🇪🇸

   We address the modeling dependence of jet taggers built using the method of Mass Unspecific Supervised Tagging, by using two different parton showering and hadronisation schemes. We find that the modeling dependence of the results - estimated by using different schemes in the design of the taggers and applying them to the same type of data - is rather small, even if the jet substructure varies significantly between the two schemes. These results add great value to the use of generic supervised taggers for new physics searches.

   hep-phEPJC(2022)·15 citations
2. 02*

   CP-Violating 2HDMs Emerging from 3-3-1 Models

   Zhiyi Fan🇯🇵 · Kei Yagyu🇯🇵

   We investigate CP violating 2 Higgs doublet models as an effective theory emerging from models with an $SU(3{)}_L\otimes U(1{)}_X$ gauge symmetry. Because of the extension of the electroweak symmetry, a characteristic structure of Yukawa interactions appears with new CP violating phases at the electroweak scale. In this scenario, the charged Higgs boson loop provides dominant and sizable contributions to the neutron electric dipole moment (nEDM) at one-loop level. We find that the prediction of the nEDM can be slightly smaller than the current upper limit, $\mathcal{O}(10^{-26})e\text{cm}$, with the mass of the charged Higgs boson and new CP violating phases to be a few hundred GeV and $\mathcal{O}(1)$, respectively, under the constraints from the meson mixings, the $B\to X_s\gamma$ decay and current LHC data.

   hep-phJHEP(2022)·9 citations
3. 03*

   $b\to c\tau {\bar{\nu }}_{e,\mu }$ contributions to $R(D^{(\ast )})$

   Shikma Bressler🇮🇱 · Federico De Vito Halevy🇮🇱 · Yosef Nir🇮🇱

   The $R(D^{(\ast )})$ puzzle stands for a $\sim 3\sigma$ violation of lepton flavor universality between the decay rates of $B\to D^{(\ast )}\tau \nu$ and $B\to D^{(\ast )}\ell \nu$, where $\ell =e,\mu$. If it is accounted for by new physics, there is no reason in general that the relevant neutrinos are, respectively, ${\nu }_{\tau }$ and ${\nu }_{\ell }$. We study whether the $\tau$ related rate could be enhanced by significant contributions to $B\to D^{(\ast )}\tau {\nu }_{\ell }$ from a class of operators in the Standard Model Effective Field Theory (SMEFT). We find the upper bounds from forbidden or rare meson decays imply that the contributions from the lepton flavor violating processes account for no more than about $4\%$ of the required shift. Yet, no fine-tuned flavor alignment is required for the new physics. Searching for the related high-$p_T$ process $pp\to {\tau }^{\pm }{\mu }^{\mp }$ can at present put a lower bound on the scale of the lepton flavor violating new physics that is a factor of $2.2$ weaker than the bound from meson decays. An exception to our conclusion arises from a specific combination of scalar and tensor SMEFT operators.

   hep-phhep-exJHEP(2022)·4 citations
4. 04*

   Correlations between the deconfining and chiral transitions in holographic QCD

   Ying-Ying Li🇨🇳 · Xing-Lin Liu🇨🇳 · Xin-Yi Liu🇨🇳 · Zhen Fang🇨🇳

   We consider an improved soft-wall AdS/QCD model coupled to an Einstein-dilaton system, which offers a way to study the deconfining and chiral transitions simultaneously. The correlation between these two transitions has been investigated in detail in the Einstein-dilaton-scalar system with the bulk scalar field representing the vacuum of matters in the flavor sector of the model. We find that the effects of the scaling dimension $\Delta$ of the dual operator of the dilaton manifest in chiral transitions, although the equation of state can all be matched with the two-flavor lattice results for $\Delta =2.5,3,3.5$ in the decoupling case of $\beta =0$. In the weak-coupling case with smaller $\beta$, both the equation of state and the chiral transition exhibit a crossover behavior and turn into first-order phase transitions with the increase of $\beta$.

   hep-phPRD(2022)·12 citations
5. 05*

   Phenomenology of a two-component dark matter model

   Yeong Gyun Kim🇰🇷 · Kang Young Lee🇰🇷 · Soo-hyeon Nam🇰🇷

   We study a two-component dark matter model consisting of a Dirac fermion and a complex scalar charged under new U(1) gauge group in the hidden sector. The dark fermion plays the dominant component of dark matter which explains the measured DM relic density of the Universe. It has no direct coupling to ordinary standard model particles, thus evading strong constraints from the direct DM detection experiments. The dark fermion is self-interacting through the light dark gauge boson and it would be possible to address that this model can be a resolution to the small scale structure problem of the Universe. The light dark gauge boson, which interacts with the standard model sector, is also stable and composes the subdominant DM component. We investigate the model parameter space allowed by current experimental constraints and phenomenological bounds. We also discuss the sensitivity of future experiments such as SHiP, DUNE and ILC, for the obtained allowed parameter space.

   hep-phhep-exPLB(2022)·4 citations
6. 06*

   Impact of recent $(g-2{)}_{\mu }$ measurement on the light CP-even Higgs scenario in general Next-to-Minimal Supersymmetric Standard Model

   Junjie Cao🇨🇳 · Jingwei Lian🇨🇳 · Yusi Pan🇨🇳 · Yuanfang Yue🇨🇳 · Di Zhang🇨🇳

   The General Next-to-Minimal Supersymmetric Standard Model (GNMSSM) is an attractive theory that is free from the tadpole problem and the domain-wall problem of $Z_3$-NMSSM, and can form an economic secluded dark matter (DM) sector to naturally predict the DM experimental results. It also provides mechanisms to easily and significantly weaken the constraints from the LHC search for supersymmetric particles. These characteristics enable the theory to explain the recently measured muon anomalous magnetic moment, $(g-2{)}_{\mu }$, in a broad parameter space that is consistent with all experimental results and at same time keeps the electroweak symmetry breaking natural. This work focuses on a popular scenario of the GNMSSM in which the next-to-lightest CP-even Higgs boson corresponds to the scalar discovered at the Large Hadron Collider (LHC). Both analytic formulae and a sophisticated numerical study show that in order to predict the scenario without significant tunings of relevant parameters, the Higgsino mass ${\mu }_{tot}\lesssim 500\mathrm{GeV}$ and $\tan \beta \lesssim 30$ are preferred. This character, if combined with the requirement to account for the $(g-2{)}_{\mu }$ anomaly, will entail some light sparticles and make the LHC constraints very tight. As a result, this scenario can explain the muon anomalous magnetic moment in very narrow corners of its parameter space.

   hep-phJHEP(2022)·22 citations
7. 07*

   Revisiting the Fermionic Dark Matter Absorption on Electron Target

   Shao-Feng Ge🇨🇳 · Xiao-Gang He🇨🇳 · Xiao-Dong Ma🇨🇳 · Jie Sheng🇨🇳

   We perform a systematic study of the fermionic DM absorption interactions on electron target in the context of effective field theory. The fermionic DM absorption is not just sensitive to sub-MeV DM with efficient energy release, but also gives a unique signature with clear peak in the electron recoil spectrum whose shape is largely determined by the atomic effects. Fitting with the Xenon1T and PandaX-II data prefers DM mass at $m_{\chi }=59$keV and 105keV, respectively, while the cut-off scale is probed up to around 1TeV. The DM overproduction in the early Universe, the invisible decay effect on the cosmological evolution, and the astrophysical X(gamma)-ray from the DM visible decays are thoroughly explored to give up-to-date constraints. With stringent bounds on the tensor and pseudo-scalar operators, the other fermionic DM operators are of particular interest at tonne-scale direct detection experiments such as PandaX-4T, XENONnT, and LZ.

   hep-phhep-exJHEP(2022)·34 citations
8. 08*

   Freeze-in Leptogenesis via Dark-Matter Oscillations

   Justin Berman🇺🇸 · Brian Shuve🇺🇸 · David Tucker-Smith🇺🇸

   We study the cosmology and phenomenology of freeze-in baryogenesis via dark-matter oscillations, taking the dark matter to couple to Standard Model leptons. We investigate viable models both with and without a $Z_2$ symmetry under which all new fields are charged. Lepton flavor effects are important for leptogenesis in these models, and we identify scenarios in which the baryon asymmetry is parametrically distinct from and enhanced relative to leptogenesis from sterile neutrino oscillations. The models we study predict the existence of new, electroweak-charged fields, and can be tested by a combination of collider searches, structure-formation studies, X-ray observations, and terrestrial low-energy tests.

   hep-phastro-ph.COPRD(2022)·9 citations
9. 09*

   Effective transverse momentum in multiple jet production at hadron colliders

   Luca Buonocore🇨🇭 · Massimiliano Grazzini🇨🇭 · Jürg Haag🇨🇭 · Luca Rottoli🇨🇭 · Chiara Savoini🇨🇭

   We consider the class of inclusive hadron collider processes in which several energetic jets are produced, possibly accompanied by colourless particles (such as Higgs boson(s), vector boson(s) with their leptonic decays, and so forth). We propose a new variable that smoothly captures the $N+1$ to $N$-jet transition. This variable, that we dub $k_T^{\mathrm{ness}}$, represents an effective transverse momentum controlling the singularities of the $N+1$-jet cross section when the additional jet is unresolved. The $k_T^{\mathrm{ness}}$ variable offers novel opportunities to perform higher-order calculations in Quantum Chromodynamics (QCD) by using non-local subtraction schemes. We study the singular behavior of the $N+1$-jet cross section as $k_T^{\mathrm{ness}}\to 0$ and, as a phenomenological application, we use the ensuing results to evaluate next-to-leading order corrections to $H$+jet and $Z$+2 jet production at the LHC. We show that $k_T^{\mathrm{ness}}$ performs extremely well as a resolution variable and appears to be very stable with respect to hadronization and multiple-parton interactions.

   hep-phPRD(2022)·22 citations
10. 10*

    Pion Photoproduction off Nucleon with Hamiltonian Effective Field Theory

    Dan Guo🇨🇳 · Zhan-Wei Liu🇨🇳

    We analyze the $\gamma N\to \pi N$ process in the negative parity channel with Hamiltonian effective filed theory which is successful in studying the nucleon resonances associated with the meson-nucleon scattering and lattice QCD simulations. We provide the scattering amplitude of pion photoproduction and extract the electric dipole amplitudes $E_{0+}$. The triquark component in $N^{\ast }(1535)$ is important for improving the consistence between our results and the experimental data.

    hep-phnucl-thPRD(2022)·15 citations
11. 11*

    Monopoles, Exotic states and Muon $g-2$ in TeV scale Trinification

    Digesh Raut🇺🇸 · Qaisar Shafi🇺🇸 · Anil Thapa🇺🇸

    We study the low energy implications of a trinification model based on the gauge symmetry $G=SU(3{)}_c\times SU(3{)}_L\times SU(3{)}_R$, without imposing gauge coupling unification. A minimal model requires two Higgs multiplets that reside in the bi-fundamental representation of $G$, and this is shown to be adequate for accommodating the Standard Model (SM) fermion masses and generate, via loop corrections and seesaw mechanism, suitable masses for the heavy neutral leptons as well as the observed SM neutrinos. We estimate a lower bound of around 15 TeV for the masses of the new down-type quarks that are required by the $SU(3{)}_L\times SU(3{)}_R$ symmetry. We examine the resonant production at the LHC of the new gauge bosons, which leads to a lower bound of 16 TeV for the symmetry breaking scale of $G$. We also show how the muon $g-2$ anomaly can be resolved in the presence of these new gauge bosons and the heavy charged leptons present in the model. Finally, the model predicts the presence of a topologically stable monopole carrying three quanta $(6\pi /e)$ of Dirac magnetic charge and mass $\gtrsim 160$ TeV. If new matter fields lying in the fundamental representations of G are included, the model predicts the presence of exotic leptons, mesons and baryons carrying fractional electric charges such as $\pm e/3$ and $\pm 2e/3$, fully compatible with the Dirac quantization condition.

    hep-phEPJC(2022)·7 citations
12. 12*

    Two-loop tensor integral coefficients in OpenLoops

    Stefano Pozzorini🇨🇭 · Natalie Schär🇨🇭 · Max F. Zoller🇨🇭

    We present a new and fully general algorithm for the automated construction of the integrands of two-loop scattering amplitudes. This is achieved through a generalisation of the open-loops method to two loops. The core of the algorithm consists of a numerical recursion, where the various building blocks of two-loop diagrams are connected to each other through process-independent operations that depend only on the Feynman rules of the model at hand. This recursion is implemented in terms of tensor coefficients that encode the polynomial dependence of loop numerators on the two independent loop momenta. The resulting coefficients are ready to be combined with corresponding tensor integrals to form scattering probability densities at two loops. To optimise CPU efficiency we have compared several algorithmic options identifying one that outperforms naive solutions by two orders of magnitude. This new algorithm is implemented in the OpenLoops framework in a fully automated way for two-loop QED and QCD corrections to any Standard Model process. The technical performance is discussed in detail for several $2\to 2$ and $2\to 3$ processes with up to order $10^5$ two-loop diagrams. We find that the CPU cost scales linearly with the number of two-loop diagrams and is comparable to the cost of corresponding real-virtual ingredients in a NNLO calculation. This new algorithm constitutes a key building block for the construction of an automated generator of scattering amplitudes at two loops.

    hep-phJHEP(2022)·19 citations
13. 13*

    Probing the $Zb\bar{b}$ anomalous couplings via exclusive $Z$ boson decay

    Hongxin Dong🇨🇳 · Peng Sun🇨🇳 · Bin Yan🇺🇸 · C.-P. Yuan🇺🇸

    We propose to utilize the exclusive $Z$-boson rare decays $Z\to {\rm Y}(ns)+\gamma$ to constrain the $Zb\bar{b}$ couplings at the HL-LHC and 100 TeV proton-proton collider. We demonstrate that the event yield of the proposed processes is sensitive to the axial-vector component of the $Zb\bar{b}$ coupling and can provide complementary information to the jet-charge weighted single-spin asymmetry measurement at the EIC and the $gg\to Zh$ production rate measurement at the LHC. By applying the NRQCD factorization formalism, we calculate the partial decay width of $Z\to {\rm Y}(ns)+\gamma$ to the NLO accuracy in strong interaction, which is found to agree with those obtained from the light-cone distribution amplitude approach. We show that the HL-LHC can break the degeneracy of the $Zb\bar{b}$ couplings, as implied by the precision electroweak data at LEP and SLC, if the signal efficiency can be improved by a factor of 1.7 from the present ATLAS analysis at the 13 TeV LHC with an integrated luminosity of $36.1{\mathrm{fb}}^{-1}$.

    hep-phhep-exPLB(2022)·16 citations
14. 14*

    Automatic computation of Feynman integrals containing linear propagators via auxiliary mass flow

    Zhi-Feng Liu🇨🇳 · Yan-Qing Ma🇨🇳

    We proposed a recipe to systematically calculate Feynman integrals containing linear propagators using the auxiliary mass flow method. The key of the recipe is to introduce a quadratic term for each linear propagator and then using differential equations to get rid of their effects. As an application, we calculated all master integrals of vacuum integrals containing a gauge link up to four loops, and we checked the results by nontrivial dimensional recurrence relations.

    hep-phPRD(2022)·32 citations
15. 15*

    Determining Feynman integrals with only input from linear algebra

    Zhi-Feng Liu🇨🇳 · Yan-Qing Ma🇨🇳

    We find that all Feynman integrals (FIs), having any number of loops, can be completely determined once linear relations between FIs are provided. Therefore, FIs computation is conceptually changed to a linear algebraic problem. Examples up to 5 loops are given to verify this observation. As a byproduct, we get a powerful method to calculate perturbative corrections in quantum field theory.

    hep-phhep-thPRL(2022)·109 citations
16. 16*

    Emergent neutrinos from heavy messengers

    Pascal Anastasopoulos (Vienna U.)🇦🇹 · Elias Kiritsis (APC, Paris and Crete U.)🇫🇷

    Fermionic bound states (mesinos) of messengers can play the role of right-handed neutrinos and due to their heavy masses they can realize the seesaw mechanism providing light and heavy sterile neutrinos. We study simple models with a single mesino to present the proof of principle. We extend our analysis to three mesino states where after the seesaw mechanism, three light and several heavy sterile neutrinos are obtained.

    hep-phhep-thJHEP(2022)·5 citations
17. 17*

    Signals for vector-like leptons in an $S_3$-symmetric 2HDM at ILC

    Indrani Chakraborty🇮🇳 · Dilip Kumar Ghosh🇮🇳 · Nivedita Ghosh🇮🇳 · Santosh Kumar Rai🇮🇳

    In this work, we explore the signals of an $S_3$-symmetric two Higgs doublet model with two generations of vector-like leptons (VLLs) at the proposed International Linear Collider (ILC). The lightest neutral component of the VLL in this model provides a viable dark matter (DM) candidate satisfying the current relic density data as well as circumventing all direct and indirect DM search constraints. Some representative benchmark points have been selected with low, medium and high DM masses, satisfying all theoretical and experimental constraints of the model and constraints coming from the DM sector. The VLLs (both neutral and charged) will be produced in pair leading to multi-lepton and multi-jet final states. We show that the ILC will prove to be a much more efficient and useful machine to hunt for such signals compared to LHC. Using traditional cut-based analysis as well as sophisticated multivariate analysis, we perform a detailed analysis of some promising channels containing mono-lepton plus di-jet, di-lepton, four-lepton and four jets along with missing transverse energy in the final state at 1 TeV ILC.

    hep-phEPJC(2022)·3 citations
18. 18*

    AMFlow: a Mathematica package for Feynman integrals computation via Auxiliary Mass Flow

    Xiao Liu🇬🇧 · Yan-Qing Ma🇨🇳

    AMFlow is a Mathematica package to numerically compute dimensionally regularized Feynman integrals via the recently proposed auxiliary mass flow method. In this framework, integrals are treated as functions of an auxiliary mass parameter and their results can be obtained by constructing and solving differential systems with respect to this parameter, in an automatic way. The usage of this package is described in detail through an explicit example of double-box family involved in two-loop $t\bar{t}$ hadroproduction.

    hep-phhep-thComput.Phys.Commun.(2023)·385 citations
19. 19*

    NLO results with operator mixing for fully heavy tetraquarks in QCD sum rules

    Ren-Hua Wu🇨🇳 · Yu-Sheng Zuo🇨🇳 · Chen-Yu Wang🇩🇪 · Ce Meng🇨🇳 · Yan-Qing Ma🇨🇳 · Kuang-Ta Chao🇨🇳

    We study the mass spectra of $\bar{Q}Q\bar{Q}Q(Q=c,b)$ systems in QCD sum rules with the complete next-to-leading order (NLO) contribution to the perturbative QCD part of the correlation functions. Instead of meson-meson or diquark-antidiquark currents, we use diagonalized currents under operator renormalization. We find that differing from conventional mesons $\bar{q}q$ and baryons $qqq$, a unique feature of the multiquark systems like $\bar{Q}Q\bar{Q}Q$ is the operator mixing or color configuration mixing induced by NLO corrections, which is crucial to understand the color structure of the states. Our numerical results show that the NLO corrections are very important for the $\bar{Q}Q\bar{Q}Q$ system, because they not only give significant contributions but also reduce the scheme and scale dependence and make Borel platform more distinct, especially for the $\bar{b}b\bar{b}b$ in the $\overline{\mathrm{MS}}$ scheme. We use currents that have good perturbation convergence in our phenomenological analysis. With the $\overline{\mathrm{MS}}$ scheme, we get three $J^{PC}=0^{++}$ states, with masses $6.35_{-0.17}^{+0.20}$ GeV, $6.56_{-0.20}^{+0.18}$ GeV and $6.95_{-0.31}^{+0.21}$ GeV, respectively. The first two seem to agree with the broad structure around $6.2\sim 6.8$ GeV measured by the LHCb collaboration in the $J/\psi J/\psi$ spectrum, and the third seems to agree with the narrow resonance $X(6900)$. For the $2^{++}$ states we find one with mass $7.03_{-0.26}^{+0.22}$ GeV, which is also close to that of $X(6900)$, and another one around $7.25_{-0.35}^{+0.21}$ GeV, which has good scale dependence but slightly large scheme dependence.

    hep-phhep-exJHEP(2022)·33 citations
20. 20*

    The see-saw portal at future Higgs factories: the role of dimension six operators

    Daniele Barducci🇮🇹 · Enrico Bertuzzo🇧🇷

    We study an extension of the Standard Model with electroweak scale right-handed singlet fermions $N$ that induces neutrino masses, plus a generic new physics sector at a higher scale $\Lambda$. The latter is parametrized in terms of effective operators in the language of the $\nu$SMEFT. We study its phenomenology considering operators up to $d=6$, where additional production and decay modes for $N$ are present in addition to those arising from the mixing with the active neutrinos. We focus on the production with four-Fermi operators and we identify the most relevant additional decay modes to be $N\to \nu \gamma$ and $N\to 3f$. We assess the sensitivity of future Higgs factories on the $\nu$SMEFT in regions of the parameter space where the new states decay promptly, displaced or are stable on detector lengths. We show that new physics scale up to $5-60$TeV can be explored, depending on the collider considered.

    hep-phJHEP(2022)·30 citations
21. 21*

    Gravitational Waves in Metastable Supersymmetry Breaking

    Chong-Sun Chu🇹🇼 · Asuka Ito🇹🇼

    If supersymmetry is broken in metastable vacua, it is not clear why we are now in there rather than supersymmetric vacua. Moreover, it is natural to expect that we were in supersymmetric vacua, which have higher symmetry than metastable vacua, in the early universe. In this paper, we reexamine and improve the previous analysis on the cosmological evolution of the vacuum structure in the ISS model of metastable supersymmetry breaking by taking into account constraints on the reheating temperature, which is needed to avoid the overproduction of gravitinos. It turns out that the desired phase transition from a supersymmetric vacuum to a metastable vacuum is allowed only in the light gravitino mass region $m_{3/2}<4.7$ eV. This is achieved by either rolling down potential or tunneling processes depending on the reheating temperature. We show that when the tunneling processes are realized, abundant gravitational waves could be produced from collisions of runaway bubbles. The resulting gravitational waves are detectable with the future gravitational wave interferometers like LISA and DECIGO.

    ↳ hep-thastro-ph.COgr-qchep-phPRD(2022)·3 citations
22. 22*

    Constrains of the axion-like particle from black hole spin superradiance

    Lei-dong Cheng🇨🇳 · Hong Zhang🇨🇳 · Shou-shan Bao🇨🇳

    The mass of the axion-like particles could be constrained by the observed black hole spin distribution. In this work, we update the previous calculations using the recently improved superradiance formula, which is much more accurate. The effect of the merger time scale is also carefully investigated with Bayesian analysis. After integration of the merger time ${\tau }_{\mathrm{M}}$, we find two favoured mass ranges $7.94\times 10^{-13}\text{eV}\le \mu \le 8.71\times 10^{-13}\text{eV}$ and $1.44\times 10^{-12}\text{eV}\le \mu \le 1.74\times 10^{-12}\text{eV}$ . These two favored ranges do not depend on the prior distribution of the ${\tau }_{\mathrm{M}}$. We also find the strength of evidence for the range $-12.80\le {\log }_{10}(\mu /\text{eV})\le -12.34$, which is excluded in the analysis with fixed ${\tau }_{\text{M}}$, could increase by several orders of magnitude with ${\tau }_{\mathrm{M}}$ averaged.

    ↳ gr-qchep-phPRD(2023)·20 citations
23. 23*

    Limits on primordial non-Gaussianities from BOSS galaxy-clustering data

    Guido D'Amico🇮🇹 · Matthew Lewandowski🇺🇸 · Leonardo Senatore🇨🇭 · Pierre Zhang🇨🇳

    We analyze the power spectrum and the bispectrum of BOSS galaxy-clustering data using the prediction from the Effective Field Theory of Large-Scale Structure at one-loop order for $\text{both}$ the power spectrum $\text{and}$ the bispectrum. With $\Lambda$CDM parameters fixed to Planck preferred values, we set limits on three templates of non-Gaussianities predicted by many inflationary models: the equilateral, the orthogonal, and the local shapes. After validating our analysis against simulations, we find $f_{\mathrm{NL}}^{equil.}=207\pm 292,f_{\mathrm{NL}}^{orth.}=-68\pm 73,f_{\mathrm{NL}}^{loc.}=52\pm 34$, at $68\%$ confidence level. These bispectrum-based constraints from Large-Scale Structure, not far from the ones of WMAP, suggest promising results from upcoming surveys.

    ↳ astro-ph.COhep-phhep-thPRD(2025)·204 citations
24. 24*

    Status update: asymptotically safe gravity-matter systems

    Astrid Eichhorn🇩🇰

    The field of asymptotically safe matter-gravity systems is maturing from the study of simple toy models to the exploration of sectors of the Standard Model and beyond. This status update reviews the current state of the art and points out open questions and future perspectives.

    ↳ gr-qchep-phhep-thNuovo Cim.C(2022)·31 citations
25. 25*

    Milky Way Satellite Census. IV. Constraints on Decaying Dark Matter from Observations of Milky Way Satellite Galaxies

    S. Mau🇺🇸 · E. O. Nadler🇺🇸 · R. H. Wechsler🇺🇸 · A. Drlica-Wagner🇺🇸 · K. Bechtol🇺🇸 · G. Green🇩🇪 · D. Huterer🇺🇸 · T. S. Li🇨🇦 · Y.-Y. Mao🇺🇸 · C. E. Martínez-Vázquez🇨🇱 · M. McNanna🇺🇸 · B. Mutlu-Pakdil🇺🇸 and 57 other authors

    We use a recent census of the Milky Way (MW) satellite galaxy population to constrain the lifetime of particle dark matter (DM). We consider two-body decaying dark matter (DDM) in which a heavy DM particle decays with lifetime $\tau$ comparable to the age of the Universe to a lighter DM particle (with mass splitting $ϵ$) and to a dark radiation species. These decays impart a characteristic "kick velocity," $V_{\mathrm{kick}}=ϵc$, on the DM daughter particles, significantly depleting the DM content of low-mass subhalos and making them more susceptible to tidal disruption. We fit the suppression of the present-day DDM subhalo mass function (SHMF) as a function of $\tau$ and $V_{\mathrm{kick}}$ using a suite of high-resolution zoom-in simulations of MW-mass halos, and we validate this model on new DDM simulations of systems specifically chosen to resemble the MW. We implement our DDM SHMF predictions in a forward model that incorporates inhomogeneities in the spatial distribution and detectability of MW satellites and uncertainties in the mapping between galaxies and DM halos, the properties of the MW system, and the disruption of subhalos by the MW disk using an empirical model for the galaxy--halo connection. By comparing to the observed MW satellite population, we conservatively exclude DDM models with $\tau <18\mathrm{Gyr}$ ($29\mathrm{Gyr}$) for $V_{\mathrm{kick}}=20\mathrm{km}{\mathrm{s}}^{-1}$ ($40\mathrm{km}{\mathrm{s}}^{-1}$) at $95\%$ confidence. These constraints are among the most stringent and robust small-scale structure limits on the DM particle lifetime and strongly disfavor DDM models that have been proposed to alleviate the Hubble and $S_8$ tensions.

    ↳ astro-ph.COastro-ph.GAhep-phApJ(2022)·47 citations
26. 26*

    Gas dynamics in dwarf galaxies as testbeds for dark matter and galaxy evolution

    Federico Lelli (INAF, Arcetri Astrophysical Observatory)🇮🇹

    Dwarf galaxies are ideal laboratories to test dark matter models and alternative theories because their dynamical mass (from observed kinematics) largely outweighs their baryonic mass (from gas and stars). In most star-forming dwarfs, cold atomic gas forms regularly rotating disks extending beyond the stellar component, thus probing the gravitational potential out to the outermost regions. Here I review several aspects of gas dynamics in dwarf galaxies, such as rotation curves, mass models, and noncircular motions. Star-forming dwarfs extend the dynamical laws of spiral galaxies to lower masses, surface densities, and accelerations. The three main dynamical laws of rotation-supported galaxies point to three distinct acceleration scales, which play different physical roles but display the same value, within uncertainties. The small scatter around these dynamical laws implies a tight coupling between baryons and dark matter in galaxies, which will be better understood with next-generation surveys that will enlarge current sample sizes by orders of magnitude.

    ↳ astro-ph.GAastro-ph.COgr-qchep-phNature Astron.(2022)·32 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.