arXiv subjects

Vigdor L. Teplitz

Publications and source records attributed to Vigdor L. Teplitz.

15 recordsLinked to original sources

arXiv2014

Supernova Bounds on the Dark Photon Using its Electromagnetic Decay

The hypothetical massive dark photon ($γ'$) which has kinetic mixing with the SM photon can decay electromagnetically to $e^+e^-$ pairs if its mass $m$ exceeds $2m_e$ and otherwise into three SM photons. These decays yield cosmological and supernovae associated signatures. We briefly discuss these signatures, particularly in connection with the supernova SN1987A and delineate the extra constraints that may then arise on the mass and mixing parameter of the dark photon. In particular, we find that for dark photon mass $m_{γ'}$ in the 5-20 MeV range, arguments based on supernova 1987A observations lead to a bound on $ε$ which is about 300 times stronger than the presently existing bounds based on energy loss arguments.

hep-ph↗

arXiv2005

Seismic Search for Strange Quark Nuggets

Bounds on masses and abundances of Strange Quark Nuggets (SQNs) are inferred from a seismic search on Earth. Potential SQN bounds from a possible seismic search on the Moon are reviewed and compared with Earth capabilities. Bounds are derived from the data taken by seismometers implanted on the Moon by the Apollo astronauts. We show that the Apollo data implies that the abundance of SQNs in the region of 10 kg to one ton must be at least an order of magnitude less than would saturate the dark matter in the solar neighborhood.

astro-ph↗

arXiv2003

Unexplained Sets of Seismographic Station Reports and A Set Consistent with a Quark Nugget Passage

In 1984 Edward Witten proposed that an extremely dense form of matter composed of up, down, and strange quarks may be stable at zero pressure (Witten, 1984). Massive nuggets of such dense matter, if they exist, may pass through the Earth and be detectable by the seismic signals they generate (de Rujula and Glashow, 1984). With this motivation we investigated over 1 million seismic data reports to the U.S. Geological Survey for the years 1990-1993 not associated with epicentral sources. We report two results: (1) with an average of about 0.16 unassociated reports per minute after data cuts, we found a significant excess over statistical expectation for sets with ten or more reports in ten minutes; and (2) in spite of a very small a priori probability from random reports, we found one set of reports with arrival times and other features appropriate to signals from an epilinear source. This event has the properties predicted for the passage of a nugget of strange quark matter (SQM) through the earth, although there is no direct confirmation from other phenomenologies.

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arXiv2000

Mirror Dark Matter and Core Density of Galaxies

We present a particle physics realization of a recent suggestion by Spergel and Steinhardt that collisional but dissipationless dark matter may resolve the core density problem in dark matter-dominated galaxies such as the dwarf galaxies. The realization is the asymmetric mirror universe model introduced to explain the neutrino puzzles and the microlensing anomaly. The mirror baryons are the dark matter particles with the desired properties. The time scales are right for resolution of the core density problem and formation of mirror stars (MACHOs observed in microlensing experiments). The mass of the region homogenized by Silk damping is between a dwarf and a large galaxy.

astro-ph↗

arXiv2000

SIMP (Strongly Interacting Massive Particle) Search

We consider laboratory experiments that can detect stable, neutral strongly interacting massive particles (SIMPs). We explore the SIMP annihilation cross section from its minimum value (restricted by cosmological bounds) to the barn range, and vary the mass values from a GeV to a TeV. We also consider the prospects and problems of detecting such particles at the Tevatron.

hep-ph↗

arXiv2000

Plasma Energy Loss into Kaluza-Klein Modes

Recently, Barger {\em et al.} computed energy losses into Kaluza Klein modes from astrophysical plasmas in the approximation of zero density for the plasmas. We extend their work by considering the effects of finite density for two plasmon processes. Our results show that, for fixed temperature, the energy loss rate per cm$^3$ is constant up to some critical density and then falls exponentially. This is true for transverse and longitudinal plasmons in both the direct and crossed channels over a wide range of temperature and density. A difficulty in deriving the appropriate covariant interaction energy at finite density and temperature is addressed. We find that, for the cases considered by Barger {\em et al.}, the zero density approximation and the neglect of other plasmon processes is justified to better than an order of magnitude.

hep-ph↗

arXiv2000

SIMP (Strongly Interacting Massive Particle) Search

hep-ph↗

arXiv1999

Mirror Matter MACHOs

We propose that the massive compact halo objects (MACHOs) observed in the recent microlensing experiments with an apparent best fit mass of about $0.5 M_{\odot}$ are objects made out of ``mirror'' baryonic matter rather than familiar baryons. Such a possibility arises naturally within the framework of mirror matter models proposed recently to accomodate the sterile neutrinos that seem necessary to solve all the neutrino puzzles simultaneusly. We show that for mirror matter parameters that fit the neutrino observations, the maximum mass of mirror stars are of order $0.5 M_{\odot}$ and their main sequence lifetime is much less than the age of the universe. They are therefore likely to be black holes. Mirror matter machos have the advantage that they do not suffer from the problems encountered in the conventional red, brown or white dwarf interpretation. The calculations also apply to the question of how the world of familiar matter would be different if all fundamental mass parameters were.

astro-ph↗

arXiv1998

IR Kuiper Belt Constraints

We compute the temperature and IR signal of particles of radius $a$ and albedo $α$ at heliocentric distance $R$, taking into account the emissivity effect, and give an interpolating formula for the result. We compare with analyses of COBE DIRBE data by others (including recent detection of the cosmic IR background) for various values of heliocentric distance, $R$, particle radius, $a$, and particle albedo, $α$. We then apply these results to a recently-developed picture of the Kuiper belt as a two-sector disk with a nearby, low-density sector (40<R<50-90 AU) and a more distant sector with a higher density. We consider the case in which passage through a molecular cloud essentially cleans the Solar System of dust. We apply a simple model of dust production by comet collisions and removal by the Poynting-Robertson effect to find limits on total and dust masses in the near and far sectors as a function of time since such a passage. Finally we compare Kuiper belt IR spectra for various parameter values.

astro-ph↗

arXiv1998

Nucleosynthesis constraints on massive, stable, strongly interacting particles

We find constraints on heavy, stable, strongly interacting massive particles (X) from searches for anomalous nuclei containing them, formed during primordial nucleosynthesis. Using existing data, we obtain a limit on the abundance ratio $C_X\equiv n_X/n_B$ in the range of $3\times 10^{-8}$ to $3\times 10^{-13}$ for masses up to 10 TeV if the $X-N$ interaction is sufficiently strong to bind in low Z nuclei. We also find a rough lower limit on the $X-N$ interaction that implies binding in nuclei with $A\geq 200$ over much of the $M_X$ range of interest, and address the relative abundance of such anomalous nuclei on Earth.

hep-ph↗

arXiv1997

Supernova Constraints on a Superlight Gravitino

In supergravity models with low supersymmetry breaking scale the gravitinos can be superlight with mass in the micro-eV to keV range. In such a case, gravitino emission provides a new cooling mechanism for protoneutron stars and therefore can provide constraints on the mass of the superlight gravitino. This happens because the coupling to matter of superlight gravitinos is dominated by its goldstino component, whose coupling to matter is inversely proportional to the scale of supersymmetry breaking and increases as the gravitino mass decreases. Present observations therefore provide lower limits on the gravitino mass. Using recently revised goldstino couplings, we find that the two dominant processes in supernova cooling are $e^+e^-\to \tilde{G}\tilde{G}$ and $γ+e^-\to e^-\tilde{G}\tilde{G}$. They lead to lower limits on the supersymmetry breaking scale $Λ_{S}$ from 160 to 500 GeV for core temperatures 30 to 60 MeV and electron chemical potentials 200 to 300 MeV. The corresponding lower limits on the gravitino mass are $.6 - 6\times 10^{-6}$ eV.

hep-ph↗

arXiv1997

Astrophysical Effects of nu+gamma-->nu+gamma+gamma and Its Crossed Processes

Recently, Dicus and Repko computed nu gamma --> nu gamma gamma for energies below the threshold for e^{+}e^{-} pair production. They found across section on the order of 10^{-52} omega ^{gamma} with gamma =10, where omega is the CMS energy of one of the initial particles in MeV. Cross sections for the crossed processes are the same to factors of order one. This note investigates the extent to which these processes could, if their result extrapolates past 1 MeV: affect supernova dynamics; cut off the energy distribution of very high energy cosmic photons and neutrinos; and possibly give rise to an observable gamma signal from scattering of neutrinos from one supernova by those of a second supernova close in space and time. We also estimate, from Supernova 1987A, that, in the region above a few MeV, gamma must fall below 8.4.

astro-ph↗

arXiv1997

Millimeter-wave Signature of Strange Matter Stars

One of the most important questions in the study of compact objects is the nature of pulsars, including whether they consist of neutron matter or strange quark matter (SQM). However, few mechanisms for distinguishing between these two possibilities have been proposed. The purpose of this paper is to show that a strange star (one made of SQM) will have a vibratory mode with an oscillation frequency of approximately 250 GHz (millimeter wave). This mode corresponds to motion of the center of the expected crust of normal matter relative to the center of the strange quark core, without distortion of either. Radiation from currents generated in the crust at the mode frequency would be a SQM signature. We also consider effects of stellar rotation, estimate power emission and signal-to-noise ratio, and discuss briefly possible mechanisms for exciting the mode.

astro-ph↗

arXiv1996

Structures in the Mirror Universe

The idea of the universe with a mirror sector having all particles and forces identical to those in the familiar sector has been proposed in the context of neutrino physics as well as superstring theories. Assuming that all the quark and charged lepton masses in the mirror universe are scaled by a common factor, $ζ$, as is required in one interpretation of the neutrino data, we investigate domains of the parameter $ζ$ where physical conditions are favorable for cooling in the age of the universe that can lead to the formation of compact structures given the initial condition $Ω_B =Ω_{\tilde{B}}$ ($\tilde{B}$ denoting the mirror baryon). In particular we ask whether there is a region in $ζ$-space for which primordial Jeans mass mirror clouds cannot cool in the present age of the universe. We find that for most of the area of interest in the parameter space, atomic hyperfine structure cooling is effective in a time period short compared to the age of the universe but long compared to the free fall time for globular-sized objects expected on the basis of simple Jeans length analysis.

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arXiv1995

Improved bounds on non-luminous matter in solar orbit

We improve, using a larger set of observations including Voyager 2 Neptune flyby data, previous bounds on the amount of dark matter (DM) trapped in a spherically symmetric distribution about the sun. We bound DM by noting that such a distribution would increase the effective mass of the sun as seen by the outer planets and by finding the uncertainty in that effective mass for Uranus and Neptune in fits to the JPL Developmental Ephermeris residuals, including optical data and those two planets' Voyager 2 flybys. We extend our previous procedure by fitting more parameters of the developmental ephemerides. Additionally, we present here the values for Pioneer 10 and 11 and Voyager 1 and 2 Jupiter ranging normal points (and incorporate these data as well). Our principal result is to limit DM in spherically symmetric distributions in orbit about the sun interior to Neptune's orbit to less than an earth mass and interior to Uranus' orbit to about 1/6 of an earth's mass.

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