Fri·Jan 8, 2021Friday·January 8, 2021

1. 01*

   Proceedings of the second MadAnalysis 5 workshop on LHC recasting in Korea

   Benjamin Fuks🇫🇷 · Pyungwon Ko🇰🇷 · Seung J. Lee (editors)🇰🇷 · Jack Y. Araz🇬🇧 · Eric Conte🇫🇷 · Robin Ducrocq🇫🇷 · Thomas Flacke🇰🇷 · Si Hyun Jeon🇰🇷 · Taejeong Kim🇰🇷 · Richard Ruiz🇧🇪 · Dipan Sengupta (conveners)🇺🇸 · Sam Bein🇩🇪 and 23 other authors

   We document the activities performed during the second MadAnalysis 5 workshop on LHC recasting, that was organised in KIAS (Seoul, Korea) on February 12-20, 2020. We detail the implementation of 12 new ATLAS and CMS searches in the MadAnalysis 5 Public Analysis Database, and the associated validation procedures. Those searches probe the production of extra gauge and scalar/pseudoscalar bosons, supersymmetry, seesaw models and deviations from the Standard Model in four-top production.

   hep-phhep-exMod.Phys.Lett.A(2021)·17 citations
2. 02*

   Adjoint SU(5) GUT model with Modular $S_4$ Symmetry

   Ya Zhao🇨🇳 · Hong-Hao Zhang🇨🇳

   We study the textures of SM fermion mass matrices and their mixings in a supersymmetric adjoint SU(5) Grand Unified Theory with modular $S_4$ being the horizontal symmetry. The Yukawa entries of both quarks and leptons are expressed by modular forms with lower weights. Neutrino sector has an adjoint SU(5) representation 24 as matter superfield, which is a triplet of $S_4$. The effective light neutrino masses is generated through Type-III and Type-I seesaw mechanism. The only common complex parameter in both charged fermion and neutrino sectors is modulus $\tau$. Down-type quarks and charged leptons have the same joint effective operators with adjoint scalar in them, and their mass discrepancy in the same generation depends on Clebsch-Gordan factor. Especially for the first two generations the respective Clebsch-Gordan factors made the double Yukawa ratio $y_d{y}_{\mu }/y_e{y}_s=12$, in excellent agreement with the experimental result. We reproduce proper CKM mixing parameters and all nine Yukawa eigenvalues of quarks and charged leptons. Neutrino masses and MNS parameters are also produced properly with normal ordering is preferred.

   hep-phJHEP(2021)·42 citations
3. 03*

   Cosmological constant as a finite temperature effect

   I. Y. Park🇺🇸

   We reexamine the cosmological constant problem in a finite temperature setup and propose an intriguing possibility of carrying out perturbative analysis by employing a renormalization scheme in which the renormalized Higgs mass (or resummed mass, to be more precise) is taken to be on the order of the CMB temperature. Our proposal hinges on the fact that although the physical value of the cosmological constant does not depend on one's renormalization scheme, whether or not a fine tuning is involved does. The cosmological constant problem is avoided in the sense that the renormalization process no longer requires finetuning. This is achieved essentially by renormalization scheme-independence of a physical quantity, which in turn is assured by bare perturbation theory. The proposal shifts the cosmological constant problem to a peculiarity of the consequent perturbation series for the Higgs mass (and other massive sectors of the Standard Model); the peculiarity is interpreted as an indicator of new physics after the expected mathematical structure of the series is scrutinized. Finite-temperature-induced complexification of the effective potential is observed and its interpretation is given. A consistency check in the cosmology context is suggested.

   hep-phInt.J.Mod.Phys.A(2022)·5 citations
4. 04*

   Gluon Gravitational Form Factors at Large Momentum Transfer

   Xuan-Bo Tong🇨🇳 · Jian-Ping Ma🇨🇳 · Feng Yuan🇺🇸

   We perform a perturbative QCD analysis of the gluonic gravitational form factors (GFFs) of the proton and pion at large momentum transfer. We derive the explicit factorization formula of the GFFs in terms of the distribution amplitudes of hadrons. At the leading power, we find that $A_g^{\pi }(t)=C_g^{\pi }(t)\sim 1/(-t)$ for pion, $A_g^p(t)\sim 1/(-t{)}^2$ and $C_g^p(t)\sim {\ln }^2(-t/{\Lambda }^2)/(-t{)}^3$ for proton, respectively, where $t$ is the momentum transfer and $\Lambda$ a non-perturbative scale to regulate the endpoint singularity in $C_g^p$ calculation. Our results provide a unique perspective of the momentum dependence of the GFFs and will help to improve our understanding of the internal pressure distributions of hadrons.

   hep-phPLB(2021)·69 citations
5. 05*

   Studying ${\mathcal{B}}_1({\frac{1}{2}}^{+})\to {\mathcal{B}}_2({\frac{1}{2}}^{+}){\ell }^{+}{\ell }^{-}$ Semi-leptonic Weak Baryon Decays with the SU(3) Flavor Symmetry

   Ru-Min Wang🇨🇳 · Yuan-Guo Xu🇨🇳 · Chong Hua🇨🇳 · Xiao-Dong Cheng🇨🇳

   Motivated by recent anomalies in FCNC $b\to s{\ell }^{+}{\ell }^{-}$, we study $B_1\to B_2{\ell }^{+}{\ell }^{-}(\ell =e,\mu ,\tau )$ semi-leptonic weak decays with the SU(3) flavor symmetry, where $B_{1,2}$ are the spin-1/2 baryons of single bottomed anti-triplet $T_{b3}$, single charmed anti-triplet $T_{c3}$ or light baryon octet $T_8$. Using the SU(3) irreducible representation approach, we first obtain the amplitude relations among different decays, and then predict the relevant not-yet measured observables of these decays. (a) We calculate the branching ratios of the $T_{b3}\to T_8{\mu }^{+}{\mu }^{-}$ and $T_{b3}\to T_8{\tau }^{+}{\tau }^{-}$ in the whole $q^2$ region and in the different $q^2$ bins by the measurement of ${\Lambda }_b^0\to {\Lambda }^0{\mu }^{+}{\mu }^{-}$. Many of them are obtained for the first time. In addition, the longitudinal polarization fractions and the leptonic forward-backward asymmetries of all $T_{b3}\to T_8{\ell }^{+}{\ell }^{-}$ decays are very similar to each other in certain $q^2$ bin due to the SU(3) flavor symmetry. (b) We analyze the upper limits of $B(T_{c3}\to T_8{\ell }^{+}{\ell }^{-})$ by using the experimental upper limits of $B({\Lambda }_c^{+}\to p{\mu }^{+}{\mu }^{-})$ and $B({\Lambda }_c^{+}\to p{e}^{+}{e}^{-})$, and find the experimental upper limit of $B({\Lambda }_c^{+}\to p{\mu }^{+}{\mu }^{-})$ giving effective bounds on the relevant SU(3) flavor symmetry parameters. The predictions of $B({\Xi }_c^0\to {\Xi }^0{e}^{+}{e}^{-})$ and $B({\Xi }_c^0\to {\Xi }^0{\mu }^{+}{\mu }^{-})$ will be different between the single-quark transition dominant contributions and the W-exchange dominant ones. (c) As for $T_8\to T_8^{\prime }{\ell }^{+}{\ell }^{-}$ decays, we analyze the single-quark transition contributions and the W-exchange contributions by using two measurements of $B({\Xi }^0\to {\Lambda }^0{e}^{+}{e}^{-})$ and $B({\Sigma }^{+}\to p{\mu }^{+}{\mu }^{-})$, and give the branching ratio predictions by assuming either single-quark transition dominant contributions or the W-exchange dominant ones.

   hep-phhep-exPRD(2021)·22 citations
6. 06*

   Gauge invariance of the vector meson mass in the Coleman-Weinberg model

   Haojie Shen🇨🇳 · Yu Cheng🇨🇳 · Wei Liao🇨🇳

   We revisit the problem of the gauge invariance in the Coleman-Weinberg model in which a $U(1)$ gauge symmetry is driven spontaneously broken by radiative corrections. It was noticed in previous work that masses in this model are not gauge invariant at one-loop order. In our analysis, we use the dressed propagators of scalars which include a resummation of the one-loop self-energy correction to the tree-level propagator. We calculate the one-loop self-energy correction to the vector meson using these dressed propagators. We find that the pole mass of the vector meson calculated using the dressed propagator is gauge invariant at the vacuum determined using the effective potential calculated with a resummation of daisy diagrams.

   hep-phhep-thPRD(2021)·3 citations
7. 07*

   Exploring properties of long-lived particles in inelastic dark matter models at Belle II

   Dong Woo Kang🇰🇷 · P. Ko🇰🇷 · Chih-Ting Lu🇰🇷

   The inelastic dark matter model is one kind of popular models for the light dark matter (DM) below $O(1)$ GeV. If the mass splitting between DM excited and ground states is small enough, the co-annihilation becomes the dominant channel for thermal relic density and the DM excited state can be long-lived at the collider scale. We study scalar and fermion inelastic dark matter models for $\mathcal{O}(1)$ GeV DM at Belle II with $U(1{)}_D$ dark gauge symmetry broken into its $Z_2$ subgroup. We focus on dilepton displaced vertex signatures from decays of the DM excited state. With the help of precise displaced vertex detection ability at Belle II, we can explore the DM spin, mass and mass splitting between DM excited and ground states. Especially, we show scalar and fermion DM candidates can be discriminated and the mass and mass splitting of DM sector can be determined within the percentage of deviation for some benchmark points. Furthermore, the allowed parameter space to explain the excess of muon $(g-2{)}_{\mu }$ is also studied and it can be covered in our displaced vertex analysis during the early stage of Belle II experiment.

   hep-phhep-exJHEP(2021)·31 citations
8. 08*

   The Higgs-portal for Dark Matter:effective field theories versus concrete realizations

   Giorgio Arcadi🇮🇹 · Abdelhak Djouadi🇪🇸 · Marumi Kado🇮🇹

   Higgs-portal effective field theories are widely used as benchmarks in order to interpret collider and astroparticle searches for dark matter (DM) particles. To assess the validity of these effective models, it is important to confront them to concrete realizations that are complete in the ultraviolet regime. In this paper, we compare effective Higgs-portal models with scalar, fermionic and vector DM with a series of increasingly complex realistic models, taking into account all existing constraints from collider and astroparticle physics. These complete realizations include the inert doublet with scalar DM, the singlet-doublet model for fermionic DM and models based on spontaneously broken dark SU(2) and SU(3) gauge symmetries for vector boson DM. We also discuss the simpler scenarios in which a new scalar singlet field that mixes with the standard Higgs field is introduced with minimal couplings to isosinglet spin--$0,\frac{1}{2}$ and 1 DM states. We show that in large regions of the parameter space of these models, the effective Higgs-portal approach provides a consistent limit and thus, can be safely adopted, in particular for the interpretation of searches for invisible Higgs boson decays at the LHC. The phenomenological implications of assuming or not that the DM states generate the correct cosmological relic density are also discussed.

   hep-phEPJC(2021)·64 citations
9. 09*

   Probing the $\Delta U=0$ Rule in Three Body Charm Decays

   Avital Dery🇺🇸 · Yuval Grossman🇺🇸 · Stefan Schacht🇬🇧 · Abner Soffer🇮🇱

   CP violation in charm decay was observed in the decays $D^0\to P^{\pm }{P}^{\mp }$ of a $D^0$ meson to two pseudoscalars. When interpreted within the SM, the results imply that the ratio of the relevant rescattering amplitudes has a magnitude and phase that are both of $O(1)$. We discuss ways to probe similar ratios in $D^0\to V^{\pm }{P}^{\mp }$ decays, where $V$ is a vector that decays to two pseudoscalars, from the Dalitz-plot analysis of time-integrated three-body decays. Compared to two-body decays, three-body decays have the advantage that the complete system can be solved without the need for time-dependent CP violation measurements or use of correlated $D^0$--${\overline{D}}^0$ production. We discuss the decays $D^0\to {\pi }^{+}{\pi }^{-}{\pi }^0$ and $D^0\to K^{+}{K}^{-}{\pi }^0$ as examples by considering a toy model of only two overlapping charged resonances, treating the underlying pseudo two-body decays in full generality.

   hep-phhep-exJHEP(2021)·30 citations
10. 10*

    Explore the Axion Dark Matter through the Radio Signals from Magnetic White Dwarf Stars

    Jin-Wei Wang🇮🇹 · Xiao-Jun Bi🇨🇳 · Run-Min Yao🇨🇳 · Peng-Fei Yin🇨🇳

    Axion as one of the promising dark matter candidates can be detected through narrow radio lines emitted from the magnetic white dwarf stars. Due to the existence of the strong magnetic field, the axion may resonantly convert into the radio photon (Primakoff effect) when it passes through a narrow region in the corona of the magnetic white dwarf, where the plasma frequency is equal to the axion mass. We show that for the magnetic white dwarf WD 2010+310, the future experiment SKA phase 1 with 100 hours of observation can effectively probe the parameter space of the axion-photon coupling $g_{a\gamma }$ up to $\sim 10^{-12}{\text{GeV}}^{-1}$ for the axion mass range of $0.2\sim 3.7\mu$eV. Note that in the low mass region ($m_a\lesssim 1.5\mu \text{eV}$), the WD 2010+310 could give greater sensitivity than the neutron star RX J0806.4-4123.

    hep-phPRD(2021)·17 citations
11. 11*

    A New Approach to Probe Non-Standard Interactions in Atmospheric Neutrino Experiments

    Anil Kumar🇮🇳 · Amina Khatun🇸🇰 · Sanjib Kumar Agarwalla🇮🇳 · Amol Dighe🇮🇳

    We propose a new approach to explore the neutral-current non-standard neutrino interactions (NSI) in atmospheric neutrino experiments using oscillation dips and valleys in reconstructed muon observables, at a detector like ICAL that can identify the muon charge. We focus on the flavor-changing NSI parameter ${\epsilon }_{\mu \tau }$, which has the maximum impact on the muon survival probability in these experiments. We show that non-zero ${\epsilon }_{\mu \tau }$ shifts the oscillation dip locations in $L/E$ distributions of the up/down event ratios of reconstructed ${\mu }^{-}$ and ${\mu }^{+}$ in opposite directions. We introduce a new variable $\Delta d$ representing the difference of dip locations in ${\mu }^{-}$ and ${\mu }^{+}$, which is sensitive to the magnitude as well as the sign of ${\epsilon }_{\mu \tau }$, and is independent of the value of $\Delta m_{32}^2$. We further note that the oscillation valley in the ($E$, $\cos \theta$) plane of the reconstructed muon observables bends in the presence of NSI, its curvature having opposite signs for ${\mu }^{-}$ and ${\mu }^{+}$. We demonstrate the identification of NSI with this curvature, which is feasible for detectors like ICAL having excellent muon energy and direction resolutions. We illustrate how the measurement of contrast in the curvatures of valleys in ${\mu }^{-}$ and ${\mu }^{+}$ can be used to estimate ${\epsilon }_{\mu \tau }$. Using these proposed oscillation dip and valley measurements, the achievable precision on $|{\epsilon }_{\mu \tau }|$ at 90% C.L. is about 2% with 500 kt$\cdot$yr exposure. The effects of statistical fluctuations, systematic errors, and uncertainties in oscillation parameters have been incorporated using multiple sets of simulated data. Our method would provide a direct and robust measurement of ${\epsilon }_{\mu \tau }$ in the multi-GeV energy range.

    hep-phhep-exphysics.ins-detJHEP(2021)·31 citations
12. 12*

    Meson and glueball spectroscopy within the graviton soft wall model

    Matteo Rinaldi🇮🇹 · Vicente Vento🇪🇸

    The graviton soft wall model (GSW) provides a unified description of the scalar glueball and meson spectra with a unique energy scale. This success has led us to extend the analysis to the description of the spectra of other hadrons. We use this model to calculate masses of the odd and even ground states of glueballs for various spins, and show that the GSW model is able to reproduce the Regge trajectory of these systems. In addition, the spectra of the $\rho$, $a_1$ and the $\eta$ mesons will be addressed. Results are in excellent agreement with current experimental data.Furthermore such an achievement is obtained without any additional parameters. Indeed, the only two parameters appearing in these spectra are those that were previously fixed by the light scalar meson and glueball spectra. Finally, in order to describe the $\pi$ meson spectrum, a suitable modification of the dilaton profile function has been included in the analysis to properly take into account the Goldstone realization of chiral symmetry. The present investigation confirms that the GSW model provides an excellent description of the spectra of mesons and glueballs with only a small number of parameters unveiling a relevant predicting power.

    hep-phPRD(2021)·35 citations
13. 13*

    Observing Light-by-Light Scattering in Vacuum with an Asymmetric Photon Collider

    Maitreyi Sangal🇩🇪 · Christoph H. Keitel🇩🇪 · Matteo Tamburini🇩🇪

    The elastic scattering of two real photons in vacuum is one of the most elusive of the fundamentally new processes predicted by quantum electrodynamics. This explains why, although it was first predicted more than eighty years ago, it has so far remained undetected. Here we show that in present-day facilities, the elastic scattering of two real photons can become detectable far off axis in an asymmetric photon-photon collider setup. This may be obtained within one day of operation time by colliding 1 mJ extreme ultraviolet pulses with the broadband gamma-ray radiation generated in nonlinear Compton scattering of ultrarelativistic electron beams with terawatt-class optical laser pulses operating at a 10 Hz repetition rate. In addition to the investigation of elastic photon-photon scattering, this technique allows us to unveil or constrain new physics that could arise from the coupling of photons to yet undetected particles, therefore opening new avenues for searches of physics beyond the standard model.

    hep-phPRD(2021)·23 citations
14. 14*

    Study of medium modified jet shape observables in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV using EPOS and JEWEL event generators

    Sumit Kumar Saha · Debojit Sarkar · Subhasis Chattopadhyay · Ashik Ikbal Sheikh · Sidharth Kumar Prasad

    The jet-medium interaction in high energy heavy ion collisions is an important phenomena to characterize the hot and dense medium produced in such collisions. The study of medium-induced modifications to the substructure of inclusive charged jets indicates a redistribution of energy inside the jet cone and provides insight into the energy loss mechanisms of jets in the medium. We investigate the in-medium modification to two jet shape observables i.e., the differential jet shape ($\rho$(r)) and the angularity (g) in the most central $Pb-Pb$ collisions at $\sqrt{s_{NN}}=2.76$ TeV using two commonly used event generators i.e., JEWEL (recoil OFF) and EPOS-3 in the jet-p${}_T$ range of 20-40 GeV/c. JEWEL with recoil OFF has been used primarily as a reference system as that has been found to explain the global jet observables satisfactorily but lacks in jet-shape variables at higher jet-radii. EPOS-3 that explains the bulk properties in such collisions quite well takes into account a hydrodynamically evolving bulk matter, jets and hard-soft interactions. A comparison between the results from these models shows that while JEWEL (recoil OFF) does not explain the distribution of lost energy at higher radii with respect to the jet-axis, EPOS-3 explains the effect quite well. However, in EPOS-3, the partonic energy loss mechanism and secondary hard-soft interactions during hadronization and hadronic cascade phase are different from the conventional jet energy loss models. The current study can, therefore, provide important new insights on mechanisms regarding the modeling of the medium and hard-soft interactions in heavy ion collisions.

    hep-phhep-ex
15. 15*

    Collider Signals of Baryogenesis and Dark Matter from $B$ Mesons: A Roadmap to Discovery

    Gonzalo Alonso-Álvarez🇨🇦 · Gilly Elor🇺🇸 · Miguel Escudero🇩🇪

    Low-scale baryogenesis could be discovered at $B$-factories and the LHC. In the $B$-Mesogenesis paradigm [G. Elor, M. Escudero, and A. E. Nelson, PRD 99, 035031 (2019), arXiv:1810.00880], the CP violating oscillations and subsequent decays of $B$ mesons in the early Universe simultaneously explain the origin of the baryonic and the dark matter of the Universe. This mechanism for baryo- and dark matter genesis from $B$ mesons gives rise to distinctive signals at collider experiments, which we scrutinize in this paper. We study CP violating observables in the $B_q^0-{\bar{B}}_q^0$ system, discuss current and expected sensitivities for the exotic decays of $B$ mesons into a visible baryon and missing energy, and explore the implications of direct searches for a TeV-scale colored scalar at the LHC and in meson-mixing observables. Remarkably, we conclude that a combination of measurements at BaBar, Belle, Belle II, LHCb, ATLAS and CMS can fully test $B$-Mesogenesis.

    hep-phastro-ph.COhep-exPRD(2021)·80 citations
16. 16*

    Revisiting the role of grooming in DIS

    Yiannis Makris🇮🇹

    We introduce a novel grooming procedure, which is an extension of the modified MassDrop tagging algorithm, tailored to the needs of deep inelastic scattering (DIS). The new algorithm, which grooms the event as a whole, takes advantage of the natural separation of current and target fragmentation in the Breit frame, in order to eliminate radiation in the beam and central rapidity regions. We study the groomed invariant mass in DIS and within soft-collinear effective theory we construct a factorization theorem for the cross-section in the back-to-back limit. In this limit we show that, up to a normalization factor, the cross-section does not depend on the incoming hadronic matrix element and we propose this measurement at HERA and the future electron-ion collider (EIC) as a probe to hadronization, precision QCD, and cold nuclear matter effects. We also give an event based definition of the Winner-Take-All axis and comment on possible applications.

    hep-phPRD(2021)·17 citations
17. 17*

    Broad excitations in a 2+1D overoccupied gluon plasma

    K. Boguslavski🇦🇹 · A. Kurkela🇳🇴 · T. Lappi🇫🇮 · J. Peuron🇮🇹

    Motivated by the initial stages of high-energy heavy-ion collisions, we study excitations of far-from-equilibrium 2+1 dimensional gauge theories using classical-statistical lattice simulations. We evolve field perturbations over a strongly overoccupied background undergoing self-similar evolution. While in 3+1D the excitations are described by hard-thermal loop theory, their structure in 2+1D is nontrivial and nonperturbative. These nonperturbative interactions lead to broad excitation peaks in spectral and statistical correlation functions. Their width is comparable to the frequency of soft excitations, demonstrating the absence of soft quasiparticles in these theories. Our results also suggest that excitations at higher momenta are sufficiently long-lived, such that an effective kinetic theory description for 2+1 dimensional Glasma-like systems may exist, but its collision kernel must be nonperturbatively determined.

    hep-phhep-latnucl-thJHEP(2021)·21 citations
18. 18*

    A renormalizable left-right symmetric model with low scale seesaw mechanisms

    A. E. Cárcamo Hernández🇨🇱 · Ivan Schmidt🇨🇱

    We propose a low scale renormalizable left-right symmetric theory that successfully explains the observed SM fermion mass hierarchy, the tiny values for the light active neutrino masses and is consistent with the lepton and baryon asymmetries of the Universe, the muon and electron anomalous magnetic moments as well as the with the constraints arising from the meson oscillations. In the proposed model the top and exotic quarks obtain masses at tree level, whereas the masses of the bottom, charm and strange quarks, tau and muon leptons are generated from a tree level Universal Seesaw mechanism, thanks to their mixings with the charged exotic vector like fermions. The masses for the first generation SM charged fermions arise from a radiative seesaw mechanism at one loop level, mediated by charged vector like fermions and electrically neutral scalars. The light active neutrino masses are produced from a one-loop level inverse seesaw mechanism mediated by electrically neutral scalar singlets and right handed Majorana neutrinos. Our model is also consistent with the experimental constraints arising from the Higgs diphoton decay rate as well as with the constraints arising from charged lepton flavor violation. We also discuss the $Z^{\prime }$ and heavy scalar production at a proton-proton collider.

    hep-phNPB(2022)·26 citations
19. 19*

    Remarks on the numerical impact of potential theoretical systematics in the prediction of QCD instanton cross sections

    Michelangelo Mangano🇨🇭

    We discuss the origin and size of potential uncertainties arising in the estimate of cross sections for the production of multiparticle final states induced by QCD instantons at the LHC.

    hep-phhep-ex2 citations
20. 20*

    Solar Mass Primordial Black Holes in Moduli Dominated Universe

    Sukannya Bhattacharya🇮🇳 · Anirban Das🇺🇸 · Koushik Dutta🇮🇳

    We explore the prospect of producing primordial black holes around the solar mass region during an early matter domination epoch. The early matter-dominated epoch can arise when a moduli field comes to dominate the energy density of the Universe prior to big bang nucleosynthesis. The absence of radiation pressure during a matter-dominated epoch enhances primordial black hole formation from the gravitational collapse of primordial density fluctuations. In particular, we find that primordial black holes are produced in the $0.1-10M_{\odot }$ mass range with a favorable choice of parameters in the theory. However, they cannot explain all of the merger events detected by the LIGO/Virgo gravitational wave search. In such a case, primordial black holes form about $4\%$ of the total dark matter abundance, of which $95\%$ belongs to the LIGO/Virgo consistent mass range. The rest of the dark matter could be in the form of particles that are produced from the decay of the moduli field during reheating.

    ↳ astro-ph.COhep-phhep-thJCAP(2021)·15 citations
21. 21*

    Net-baryon number fluctuations

    C. Schmidt🇩🇪 · J. Goswami🇩🇪 · G. Nicotra🇩🇪 · F. Ziesché🇩🇪 · P. Dimopoulos🇮🇹 · F. Di Renzo🇮🇹 · S. Singh🇮🇹 · K. Zambello🇮🇹

    The appearance of large, none-Gaussian cumulants of the baryon number distribution is commonly discussed as a signal for the QCD critical point. We review the status of the Taylor expansion of cumulant ratios of baryon number fluctuations along the freeze-out line and also compare QCD results with the corresponding proton number fluctuations as measured by the STAR Collaboration at RHIC. To further constrain the location of a possible QCD critical point we discuss poles of the baryon number fluctuations in the complex plane. Here we use not only the Taylor coefficients obtained at zero chemical potential but perform also calculations of Taylor expansion coefficients of the pressure at purely imaginary chemical potentials.

    ↳ hep-lathep-phnucl-exnucl-thActa Phys. Pol. B Proc. Suppl. 14, 241 (2…·19 citations
22. 22*

    Coalescing primordial binary black holes with log-normal mass spectrum

    Konstantin Postnov (SAI Moscow U.)🇷🇺 · Alexander Dolgov (Novosibirsk U.)🇷🇺 · Nikita Mitichkin (Moscow U.)🇷🇺 · Ivan Simkin (Baumann Technical U.)🇷🇺

    Primordial black holes created in the early Universe can constitute a substantial fraction of dark matter and serve as seeds for early galaxy formation. Binary primordial black holes with masses of the order of a few dozen solar masses can explain the observed LIGO/Virgo gravitational-wave events. In this Letter, we show that primordial black holes with log-normal mass spectrum centered at $M_0\simeq 15-17M_{\odot }$ simultaneously explain both the chirp mass distribution of the detected LIGO/Virgo binary black holes and the differential chirp mass distribution of merging binaries as inferred from the LIGO/Virgo observations. The obtained parameters of log-normal mass spectrum of primordial black holes also give the fraction of seeds with $M\gtrsim 10^4{M}_{\odot }$ required to explain the observed population of supermassive black holes at $z=6-7$.

    ↳ astro-ph.HEhep-ph4 citations
23. 23*

    Probing the dynamics of chiral SU(N) gauge theories via generalized anomalies

    Stefano Bolognesi🇮🇹 · Kenichi Konishi🇮🇹 · Andrea Luzio🇮🇹

    We study symmetries and dynamics of chiral $SU(N)$ gauge theories with matter Weyl fermions in a two-index symmetric ($\psi$) or anti-symmetric tensor ($\chi$) representation, together with $N\pm 4+p$ fermions in the anti-fundamental ($\eta$) and $p$ fermions in the fundamental ($\xi$) representations. They are known as the Bars-Yankielowicz (the former) and the generalized Georgi-Glashow models (the latter). The conventional 't Hooft anomaly matching algorithm is known to allow a confining, chirally symmetric vacuum in all these models, with a simple set of massless baryonlike composite fermions describing the infrared physics. We analyzed recently one of these models ($\psi \eta$ model), by applying the ideas of generalized symmetries and the consequent, stronger constraints involving certain mixed anomalies, finding that the confining, chirally symmetric, vacuum is actually inconsistent. In the present paper this result is extended to a wider class of the Bars-Yankielowicz and the generalized Georgi-Glashow models. It is shown that for all these models with $N$ and $p$ both even, at least, the generalized anomaly matching requirement forbids the persistence of the full chiral symmetries in the infrared if the system confines. The most natural and consistent possibility is that some bifermion condensates form, breaking the color gauge symmetry dynamically, together with part of the global symmetry.

    ↳ hep-thhep-phPRD(2021)·33 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.