1010.4261
Supersymmetric monojets at the LHC
Allanach, Grab, Haber
Sypersymmetric monojets may be produced at the LHC by qg => squark neutralino => q neutralino neutralino, that leads to jet recoiling against missing transverse momentum. Do some calculations on possible precision to which one can ascertain the neutralino squark q coupling via the rate for monojet events. This contains information on the composition of the neutralino and helps bound DM direct detection X-sections and the DM relic density of the neutralino. Also checks supersymmetric relation between gauge coupling and gaugino-q-squark couplings.
* phenomenology.
1101.2028
Planck Early Results XVIII: The power spectrum of cosmic infrared background anisotropies
Planck collaboration
Use low extinction with 140 sq deg, determine l=200 to 2000 multipole at 4 frequencies. Use H I as tracer of thermal dust emission to reduce galactic dust emission; use 143 GHz Planck maps to clean out CMB anisotropies. Measure correlated CIB structure across frequencies. Correlation decreases with increasing frequency separation due to high-z galaxies to CIB increases with wavelengths. No significanat difference bewteen the frequencey spectrum of CIB anisotropies and CIB mean. Data rule out the linear scale- and z- independent bias model of clustering. Non-linear corrections are significant. Alternative model: double dusty galaxy (parametric evolution) with a halo-model approach. Provides an excellent fit to the measured anisotropy angular power spectra; different halo occupation distribution required at each frequency (consistent with different frequency corresponding to different z). Half of l=2000 power comes from z<0.8 (875 GHz) and z<1.5 (545 GHz), while 90% come from z>2 at 353 and 217 GHz.
* cool results.
1101.5287
Computation approach for CMB bispectrum from primordial magnetic fields
Shiraishi, Nitta, Yokoyama, Ichiki, Takahashi
Calculation for constraint on the magnetic field strength through CMB temperature bispectrum of vector modes induced from primordial magnetic fields. CMB bispectrum induced from the statistical-isotropic primordial vector fluctuations can also be described as an angle-averaged from.
1107.1540
Observational test of inflation in loop quantum cosmology
Bojowald, Calcagni, Tsujikawa
* loop quantum cosmology: A finite, symmetry-reduced model of loop quantum gravity that predicts a quantum bridge between contracting and expanding cosmological branches. Successes: emergence of a possible mechanism for cosmic inflation, resolution of gravitational singularities, development of semi-classical Hamiltonians. Started by Bojowald and Ashtekar at Penn State.
* loop quantum gravity: quantum theory of spacetime which attempts to reconcile the theories of quantum mechanics and general relativity. Preserves many important features of GR, while simultaneously employing quantization of both space and time at the Planck scale. LQG tries to establish a quantum theory of gravity in which the space itself becomes quantized.
Power spectra of scalar and tensor perturbations generated during inflation in loop quantum cosmology (LQC). Can generate large running spectral indices, generally leading to enhancement of power at large scales. LQC quadratic correction still can be compatible with WMAP7, but the quartic potential is in tension with observations. Upper bound on delta(k0), insensitive to the choice of inflaton potentials.
1103.5378
The Flare-energy distributions generated by kink-unstable ensembles of Zero-net-current coronal loops
Bareford, Browning, Van der Linden
* yikes, the sun and its corona!
Investigate the plausibility of the nanoflare hypothesis (the 1e6K temperature of the corona is due to nanoflares that occur throughout the solar atmosphere--beyond current observational abilities). Construct a MHD model that can derive the energy of nanoflare from an ideal kink instability. Energy-releasing instability is captured by an instability threshold. Result (after some more construction): nanoflare energy distribution. Vary stuff, obtain different distributions. Heating rate obtained is just sufficient for coronal heating. Kink instability cannot be associated with critical magnetic twist value.
1104.3688
Pre-Big-Bang cosmology and circles in the CMB
Nelson, Wilson-Ewing
Circles in CMB can be formed by gravitational wave pulse emitted in pre-BB phase, interacting with the last scattering surface. Derive typical ring width, concentric angular separation, expected distribution. Apply to conformal cyclic cosmology, ekpyrotic cosmology, loop quantum cosmology with and without inflation. Allow differentiation between various pre-BB cosmological models. Methods to determine whether observed rings are due to pre-BB energetic events.
* The physical mechanism of gravitational wave pulse interacting with the LSS is just gravity, right?
1107.0049
How peculiar was the recent extended minimum - a hint towards double minima
Jain, Tripathy, Hill
* okay, I assume they're talking about the sun, but the title is really, really vague on the subject. It's actually about the seismic minima. (presumably correlated to the solar cycle?)
Helioseismic low- and intermediate-degree mode frequencies show different epochs of seismic minima, depending on instruments. Use six identical instruments (Global Oscillation Network Group) continuously collecting data for 15 years to investigate epoch of minimum in solar oscillation frequencies. Range 0<l<120, frequency 2-3.5 mHz. There are two minima in oscillation frequencies, depending on the lower turning point radius of the propagating wave. Identify beginning of cycle 24--contrasts to 23 where the epoch of minimum did not change with latitude or depth. Hint of possible role of the relic magnetic field modifying oscillation frequencies of modes sampling deeper layers.
* I don't think they said anything about double minima in the abstract.
0806.4481
Hubble's cosmology: from a finite expanding universe to a static endless universe
Assis, Neves, Soares
Hubble was cautious about accepting big bang.
* phenomenology.
1101.2028
Planck Early Results XVIII: The power spectrum of cosmic infrared background anisotropies
Planck collaboration
Use low extinction with 140 sq deg, determine l=200 to 2000 multipole at 4 frequencies. Use H I as tracer of thermal dust emission to reduce galactic dust emission; use 143 GHz Planck maps to clean out CMB anisotropies. Measure correlated CIB structure across frequencies. Correlation decreases with increasing frequency separation due to high-z galaxies to CIB increases with wavelengths. No significanat difference bewteen the frequencey spectrum of CIB anisotropies and CIB mean. Data rule out the linear scale- and z- independent bias model of clustering. Non-linear corrections are significant. Alternative model: double dusty galaxy (parametric evolution) with a halo-model approach. Provides an excellent fit to the measured anisotropy angular power spectra; different halo occupation distribution required at each frequency (consistent with different frequency corresponding to different z). Half of l=2000 power comes from z<0.8 (875 GHz) and z<1.5 (545 GHz), while 90% come from z>2 at 353 and 217 GHz.
* cool results.
1101.5287
Computation approach for CMB bispectrum from primordial magnetic fields
Shiraishi, Nitta, Yokoyama, Ichiki, Takahashi
Calculation for constraint on the magnetic field strength through CMB temperature bispectrum of vector modes induced from primordial magnetic fields. CMB bispectrum induced from the statistical-isotropic primordial vector fluctuations can also be described as an angle-averaged from.
1107.1540
Observational test of inflation in loop quantum cosmology
Bojowald, Calcagni, Tsujikawa
* loop quantum cosmology: A finite, symmetry-reduced model of loop quantum gravity that predicts a quantum bridge between contracting and expanding cosmological branches. Successes: emergence of a possible mechanism for cosmic inflation, resolution of gravitational singularities, development of semi-classical Hamiltonians. Started by Bojowald and Ashtekar at Penn State.
* loop quantum gravity: quantum theory of spacetime which attempts to reconcile the theories of quantum mechanics and general relativity. Preserves many important features of GR, while simultaneously employing quantization of both space and time at the Planck scale. LQG tries to establish a quantum theory of gravity in which the space itself becomes quantized.
Power spectra of scalar and tensor perturbations generated during inflation in loop quantum cosmology (LQC). Can generate large running spectral indices, generally leading to enhancement of power at large scales. LQC quadratic correction still can be compatible with WMAP7, but the quartic potential is in tension with observations. Upper bound on delta(k0), insensitive to the choice of inflaton potentials.
1103.5378
The Flare-energy distributions generated by kink-unstable ensembles of Zero-net-current coronal loops
Bareford, Browning, Van der Linden
* yikes, the sun and its corona!
Investigate the plausibility of the nanoflare hypothesis (the 1e6K temperature of the corona is due to nanoflares that occur throughout the solar atmosphere--beyond current observational abilities). Construct a MHD model that can derive the energy of nanoflare from an ideal kink instability. Energy-releasing instability is captured by an instability threshold. Result (after some more construction): nanoflare energy distribution. Vary stuff, obtain different distributions. Heating rate obtained is just sufficient for coronal heating. Kink instability cannot be associated with critical magnetic twist value.
1104.3688
Pre-Big-Bang cosmology and circles in the CMB
Nelson, Wilson-Ewing
Circles in CMB can be formed by gravitational wave pulse emitted in pre-BB phase, interacting with the last scattering surface. Derive typical ring width, concentric angular separation, expected distribution. Apply to conformal cyclic cosmology, ekpyrotic cosmology, loop quantum cosmology with and without inflation. Allow differentiation between various pre-BB cosmological models. Methods to determine whether observed rings are due to pre-BB energetic events.
* The physical mechanism of gravitational wave pulse interacting with the LSS is just gravity, right?
1107.0049
How peculiar was the recent extended minimum - a hint towards double minima
Jain, Tripathy, Hill
* okay, I assume they're talking about the sun, but the title is really, really vague on the subject. It's actually about the seismic minima. (presumably correlated to the solar cycle?)
Helioseismic low- and intermediate-degree mode frequencies show different epochs of seismic minima, depending on instruments. Use six identical instruments (Global Oscillation Network Group) continuously collecting data for 15 years to investigate epoch of minimum in solar oscillation frequencies. Range 0<l<120, frequency 2-3.5 mHz. There are two minima in oscillation frequencies, depending on the lower turning point radius of the propagating wave. Identify beginning of cycle 24--contrasts to 23 where the epoch of minimum did not change with latitude or depth. Hint of possible role of the relic magnetic field modifying oscillation frequencies of modes sampling deeper layers.
* I don't think they said anything about double minima in the abstract.
0806.4481
Hubble's cosmology: from a finite expanding universe to a static endless universe
Assis, Neves, Soares
Hubble was cautious about accepting big bang.
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