Unified Emergence of Energy Scales and Cosmic Inflation

In the quest for unification of the Standard Model with gravity, classical scale invariance can be utilized to dynamically generate the Planck mass $M_\mathrm{Pl}$. Then, the relation of Planck scale physics to the scale of electroweak symmetry breaking $\mu_H$ requires further explanation. In this paper, we propose a model that uses the spontaneous breaking of scale invariance in the scalar sector as a unified origin for dynamical generation of both scales. Using the Gildener-Weinberg approximation, only one scalar acquires a vacuum expectation value of $v_S \sim (10^{16-17})\,\mathrm{GeV}$, thus radiatively generating $M_\mathrm{Pl} \approx \beta_S^{1/2} v_S$ and $\mu_H$ via the neutrino option with right handed neutrino masses $m_N = y_M v_S \sim 10^7 \,\mathrm{GeV}$. Consequently, active SM neutrinos are given a mass with the inclusion of a type-I seesaw mechanism. Furthermore, we adopt an unbroken $Z_2$ symmetry and a $Z_2$-odd set of right-handed Majorana neutrinos $\chi$ that do not take part in the neutrino option and are able to produce the correct dark matter relic abundance (dominantly) via inflaton decay. The model also describes cosmic inflation and the inflationary CMB observables are predicted to interpolate between those of $R^2$ and linear chaotic inflationary model and are thus well within the strongest experimental constraints.Comment: 21+10 pages, 11 figures, 1 table, v2: matches published versio

The Sloan Bright Arcs Survey: Four Strongly Lensed Galaxies with Redshift >2

We report the discovery of four very bright, strongly-lensed galaxies found via systematic searches for arcs in Sloan Digital Sky Survey Data Release 5 and 6. These were followed-up with spectroscopy and imaging data from the Astrophysical Research Consortium 3.5m telescope at Apache Point Observatory and found to have redshift $z>2.0$. With isophotal magnitudes $r = 19.2 - 20.4$ and 3\arcsec-diameter magnitudes $r = 20.0 - 20.6$, these systems are some of the brightest and highest surface brightness lensed galaxies known in this redshift range. In addition to the magnitudes and redshifts, we present estimates of the Einstein radii, which range from 5.0 \arcsec to 12.7 \arcsec, and use those to derive the enclosed masses of the lensing galaxies

UTM and D-NET: NASA and JAXA's Collaborative Research on Integrating Small UAS with Disaster Response Efforts

Natural disasters, such as flooding, wildfire, hurricane, tornadoes, earthquakes and tsunamis, pose challenges in preserving human life and minimizing the damages to a region. During catastrophic events, timely response of disaster relief personnel, an efficient deployment of resources in the recovery effort, and coordinated information sharing amongst different relief agencies can make a substantial difference in responding to those impacted by the disaster. Many relief activities currently utilize both ground personnel and manned airborne assets during different phases of the disaster response. Typically, multiple organizations support relief activities and this often creates logistics coordination challenges between agencies which can result in wasted time or resources. The Japan Aerospace Exploration Agency (JAXA) has been developing an "Integrated aircraft operation system for disaster relief (D-NET)", which assists collection and sharing of disaster information through the integrated operation of aircraft such as helicopters, aircraft, and satellites, for efficient and safe rescue operations by disaster relief aircraft. Due to the advancement in unmanned aircraft systems (UAS) technologies, public safety organizations have started incorporating small UAS (sUAS) as an asset in their disasters response activities. To address the airspace integration challenges of the influx of sUAS in the United States the National Aeronautics and Space Administration (NASA), under the UAS Traffic Management (UTM) project, has been engaged in research to enable large-scale commercial applications of sUAS operating in low altitude airspace. This paper presents the integration of D-NET, which incorporate sUAS in the planning, information sharing, and operation support of disasters response activities, and UTM, which provides airspace management to enable large scale high density operations. The integration of the DNET and UTM systems enables coordination, data sharing, and airspace management to improve the timeliness of the disaster response, enable relief organization to reduce cost and overhead by using UAS assets and still maintain airspace safety during the relief activities

Discovery of A Very Bright, Strongly-Lensed z=2 Galaxy in the SDSS DR5

We report on the discovery of a very bright z = 2.00 star-forming galaxy that is strongly lensed by a foreground z=0.422 luminous red galaxy (LRG). This system was found in a systematic search for bright arcs lensed by LRGs and brightest cluster galaxies in the Sloan Digital Sky Survey Data Release 5 sample. Follow-up observations on the Subaru 8.2m telescope on Mauna Kea and the Astrophysical Research Consortium 3.5m telescope at Apache Point Observatory confirmed the lensing nature of this system. A simple lens model for the system, assuming a singular isothermal ellipsoid mass distribution, yields an Einstein radius of 3.82 +/- 0.03 arcsec or 14.8 +/- 0.1 kpc/h at the lens redshift. The total projected mass enclosed within the Einstein radius is 2.10 +/- 0.03 x 10^12 M_sun/h, and the magnification factor for the source galaxy is 27 +/- 1. Combining the lens model with our gVriz photometry, we find an (unlensed) star formation rate for the source galaxy of 32 M_sun/h / yr, adopting a fiducial constant star formation rate model with an age of 100 Myr and E(B-V) = 0.25. With an apparent magnitude of r = 19.9, this system is among the very brightest lensed z >= 2 galaxies, and provides an excellent opportunity to pursue detailed studies of the physical properties of an individual high-redshift star-forming galaxy.Comment: 31 pages, 12 figures, 4 tables, submitted to Ap

Lift-off dynamics in a simple jumping robot

We study vertical jumping in a simple robot comprising an actuated mass-spring arrangement. The actuator frequency and phase are systematically varied to find optimal performance. Optimal jumps occur above and below (but not at) the robot's resonant frequency $f_0$. Two distinct jumping modes emerge: a simple jump which is optimal above $f_0$ is achievable with a squat maneuver, and a peculiar stutter jump which is optimal below $f_0$ is generated with a counter-movement. A simple dynamical model reveals how optimal lift-off results from non-resonant transient dynamics.Comment: 4 pages, 4 figures, Physical Review Letters, in press (2012