Statistical approach to Higgs boson couplings in the standard model effective field theory
Not Available
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Ellipsoidal geometry in asteroid thermal models - The standard radiometric model
The major consequences of ellipsoidal geometry in an othewise standard radiometric model for asteroids are explored. It is shown that for small deviations from spherical shape a spherical model of the same projected area gives a reasonable aproximation to the thermal flux from an ellipsoidal body. It is suggested that large departures from spherical shape require that some correction be made for geometry. Systematic differences in the radii of asteroids derived radiometrically at 10 and 20 microns may result partly from nonspherical geometry. It is also suggested that extrapolations of the rotational variation of thermal flux from a nonspherical body based solely on the change in cross-sectional area are in error.
Brown, R. H.↗
Ion transport and loss in the earth's quiet ring current. I - Data and standard model
A study of the transport and loss of ions in the earth's quiet time ring current, in which the standard radial diffusion model developed for the high-energy radiation belt particles is compared with the measurements of the lower-energy ring current ions, is presented. The data set provides ionic composition information in an energy range that includes the bulk of the ring current energy density, 1-300 keV/e. Protons are found to dominate the quiet time energy density at all altitudes, peaking near L of about 4 at 60 keV/cu cm, with much smaller contributions from O(+) (1-10 percent), He(+) (1-5 percent), and He(2+) (less than 1 percent). A minimization procedure is used to fit the amplitudes of the standard electric radial diffusion coefficient, yielding 5.8 x 10 exp -11 R(E-squared)/s. Fluctuation ionospheric electric fields are suggested as the source of the additional diffusion detected.
Sheldon, R. B.↗
On dark matter interactions with the Standard Model through an anomalous Z'
We report on electroweak scale Dark Matter (DM) whose interactions with baryonic matter are mediated by a heavy anomalous Z'. We emphasize that when the DM is a Majorana particle, its low-velocity annihilations are dominated by loop suppressed annihilations into the gauge bosons, rather than by p-wave or chirally suppressed annihilations into the SM fermions. Because the Z' is anomalous, these kinds of DM models can be realized only as effective field theories (EFTs) with a well-defined cutoff, where heavy spectator fermions restore gauge invariance at high energies. We formulate these EFTs, estimate their cutoff and properly take into account the effect of the Chern-Simons terms one obtains after the spectator fermions are integrated out. We find that, while for light DM collider and direct detection experiments usually provide the strongest bounds, the bounds at higher masses are heavily dominated by indirect detection experiments, due to strong annihilation into W + W -, ZZ, Zγ and possibly into gg and γγ. We reiterate that these annihilation channels are generically significant because of the structure of the EFT, and therefore these models are prone to strong indirect detection constraints. Although we focus on selected Z' models for illustrative purposes, our setup is completely generic and can be used for analyzing the predictions of any anomalous Z'-mediated DM model with arbitrary charges.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Electroweak corrections to Higgs boson decays to γ γ and W + W − in standard model EFT
Not Available
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Probing Physics beyond the Standard Model through Combined Analyses of Next-generation Type Ia Supernova, Cosmic Microwave Background, and Baryon Acoustic Oscillation Surveys
Observations of Type Ia supernovae (SNe Ia), which probe the late Universe, together with baryon acoustic oscillations (BAO) and the cosmic microwave background (CMB), which probe the intermediate and early epochs, provide complementary constraints on the expansion history of the Universe. In this work, we forecast constraints on dark energy and other extensions to the standard cosmological model by combining the SN Ia sample expected from the Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST), data from current and forthcoming CMB surveys, and BAO measurements from the Dark Energy Spectroscopic Instrument (DESI). For the CMB, we use temperature, polarization, and lensing power spectra (TT/EE/TE/ϕϕ) from the South Pole Telescope, the planned Advanced Simons Observatory, and a CMB-S4–like experiment. We derive constraints on ΛCDM and its extensions involving the dark energy equation-of-state parameters (w 0 , w a ) and the sum of neutrino masses ∑m ν using a Markov Chain Monte Carlo (MCMC) sampling framework. We find that the LSST Year 3 SN Ia sample can improve upon the DES Year 5 dark energy constraints by a factor of 2−2.5×, with the gains driven primarily by the significantly higher SN Ia density in the LSST sample. Similarly, DESI-DR3 shows up to a 1.8× improvement on dark energy parameters over DR2, driven largely by the substantial increase in the low-redshift sample. Combining CMB with LSST-Y3-SN Ia and DESI-DR3-BAO yields σ(w 0 ) = 0.028 and σ(w a ) = 0.11 for w 0 w a CDM cosmology with the results being largely independent of the CMB dataset. The constraints weaken by 10%–30% when freeing ∑m ν and spatial curvature. Moreover, the joint analysis of the three datasets can enable a 2σ–3σ detection of ∑m ν .
Raghunathan, Srinivasan [University of California;↗
A perturbative approach to the redshift space correlation function: beyond the Standard Model
We extend our previous redshift space power spectrum code to the redshift space correlation function. Here we focus on the Gaussian Streaming Model (GSM). Again, the code accommodates a wide range of modified gravity and dark energy models. For the non-linear real space correlation function used in the GSM we use the Fourier transform of the RegPT 1-loop matter power spectrum. We compare predictions of the GSM for a Vainshtein screened and Chameleon screened model as well as GR. These predictions are compared to the Fourier transform of the Taruya, Nishimichi and Saito (TNS) redshift space power spectrum model which is fit to N-body data. We find very good agreement between the Fourier transform of the TNS model and the GSM predictions, with ≤ 6% deviations in the first two correlation function multipoles for all models for redshift space separations in 50Mpc h ≤ s ≤ 180Mpc/ h . Excellent agreement is found in the differences between the modified gravity and GR multipole predictions for both approaches to the redshift space correlation function, highlighting their matched ability in picking up deviations from GR. We elucidate the timeliness of such non-standard templates at the dawn of stage-IV surveys and discuss necessary preparations and extensions needed for upcoming high quality data.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Generic Construction of the Standard Model Gauge Group and Matter Representations in F-theory
In this work, we describe general classes of 6D and 4D F-theory models with gauge group (SU(3)×SU(2)×U(1))/Z 6 . For 6D F-theory models with no tensor multiplets, we prove that this set of constructions gives all possible consistent supergravity theories with this gauge group and the corresponding generic matter representations, which include those of the MSSM. We expect, though do not prove, that these models are similarly generic for 6D theories with tensor multiplets and for 4D N=1 supergravity theories. Finally, the models in the largest class of these constructions come from deforming an underlying geometry with SU(4)×SU(3)×SU(2), corresponding to Higgsing on three bifundamental fields.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Field-parallel Acceleration: Comment on the Paper “Electric Currents on the Flare Ribbons: Observations and Standard Model” by Janvier et al. (2014, ApJ, 788, 60)
It is proposed that the coincidence of higher brightness and upward electric current observed by Janvier et al. during a flare indicates electron acceleration by field-parallel potential drops sustained by extremely strong field-aligned currents of order 10{sup 4} A m{sup −2}. A few consequences are discussed here.
79 ASTRONOMY AND ASTROPHYSICS↗
FOSS CAD for the Compact Verilog-A Model Standardization in Open Access PDKs
This is a conference paper about open source tools for circuit simulation and model compilers.
Grabinski, Wladek↗
Neutrino oscillation phenomenology in the standard model and beyond
Over the last 20 years measurements of neutrino oscillation parameters have become very precise. In the standard neutrino oscillation picture most of the parameters are measured at the percent level. In this thesis we study neutrino oscillations in the standard picture and beyond. We analyze data from all types of neutrino oscillation experiments to obtain a global picture of neutrino oscillations. The remaining unknowns in the standard picture are the value of the CP-violating phase $\delta$, the octant of the atmospheric angle $\theta_{23}$ and the neutrino mass ordering. We discuss the current status of these unknowns and also comment on how well future experiments will do in measuring these quantities, where we discuss new facilities which will observe accelerator, atmossperic and reactor neutrinos. Using oscillation data it is possible to bound a possible violation of the CPT symmetry in the neutrino sector. This is done by performing a fit to neutrino and antineutrino oscillation data separately. We also address the capability of the future experiment DUNE to this scenario. We show that DUNE could improve some of the current bounds considerably. We discuss the sensitivity of DUNE together with the next generation reactor neutrino experiment JUNO to measure quasi-Dirac neutrino oscillations. We find that the future experiments will be able to bound the important quantities, mostly unbounded by current data. Finally, we discuss atmospheric neutrinos at the next generation neutrino telescope ORCA. We show that ORCA will put the best bounds on the invisible neutrino decay of $\nu_3$, coming from neutrino oscillation experiments. We also find that, a scenario like this would not affect the standard measurements of ORCA, namely the determination of the atmospheric neutrino oscillation parameters and the measurement of the neutrino mass ordering.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Beyond the Standard Model Explanations of GW190521
The LIGO-Virgo Collaboration has recently announced the detection of a heavy binary black hole merger, with component masses that are difficult to account for in standard stellar structure theory. In this Letter, we propose several explanations based on models of new physics, including new light particle losses, modified gravity, large extra dimensions, and a small magnetic moment of the neutrino. Each of these affect the physics of the pair instability differently, leading to novel mechanisms for forming black holes inside the mass gap.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Primordial lithium and the standard model(s)
The results of new theoretical work on surface Li-7 and Li-6 evolution in the oldest halo stars are presented, along with a new and refined analysis of the predicted primordial Li abundance resulting from big-bang nucleosynthesis. This makes it possible to determine the constraints which can be imposed on cosmology using primordial Li and both standard big-bang and stellar-evolution models. This leads to limits on the baryon density today of 0.0044-0.025 (where the Hubble constant is 100h km/sec Mpc) and imposes limitations on alternative nucleosynthesis scenarios.
Deliyannis, Constantine P.↗
Testing the Standard Model with the Primordial Inflation Explorer
The Primordial Inflation Explorer is an Explorer-class mission to measure the gravity-wave signature of primordial inflation through its distinctive imprint on the linear polarization of the cosmic microwave background. PIXIE uses an innovative optical design to achieve background-limited sensitivity in 400 spectral channels spanning 2.5 decades in frequency from 30 GHz to 6 THz (1 cm to 50 micron wavelength). The principal science goal is the detection and characterization of linear polarization from an inflationary epoch in the early universe, with tensor-to-scalar ratio r < 10A{-3) at 5 standard deviations. The rich PIXIE data set will also constrain physical processes ranging from Big Bang cosmology to the nature of the first stars to physical conditions within the interstellar medium of the Galaxy. I describe the PIXIE instrument and mission architecture needed to detect the inflationary signature using only 4 semiconductor bolometers.
Kogut, Alan J.↗
Semileptonic tau decays beyond the Standard Model
Hadronic τ decays are studied as probe of new physics. We determine the dependence of several inclusive and exclusive τ observables on the Wilson coefficients of the low-energy effective theory describing charged-current interactions between light quarks and leptons. The analysis includes both strange and non-strange decay channels. The main result is the likelihood function for the Wilson coefficients in the tau sector, based on the up-to-date experimental measurements and state-of-the-art theoretical techniques. The likelihood can be readily combined with inputs from other low-energy precision observables. We discuss a combination with nuclear beta, baryon, pion, and kaon decay data. In particular, we provide a comprehensive and model-independent description of the new physics hints in the combined dataset, which are known under the name of the Cabibbo anomaly.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
Associated Higgs boson production with Z boson in the minimal U(1) extended Standard Model
Not Available
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
Matching the Standard Model to heavy-quark effective theory and nonrelativistic QCD
We find the leading electroweak corrections to the Lagrangians of heavy-quark effective theory and nonrelativistic QCD. These corrections appear in the Wilson coefficients of the two- and four-quark operators and are considered here at one-loop order through $\mathscr{O}(1/m^3)$ and $\mathscr{O}(1/m^2)$, respectively. The two-quark operators through this order include new parity violating terms, which we derive analogously to the parity preserving QCD result at one-loop order.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗