Astrophysics and Astronomy | Open Access Articles

Unidirectional Lasing Emerging From Frozen Light In Nonreciprocal Cavities, Hamidreza Ramezani, S. Kalish, I. Vitebskiy, T. Kottos

Physics & Astronomy Faculty Publications

We introduce a class of unidirectional lasing modes associated with the frozen mode regime of nonreciprocal slow-wave structures. Such asymmetric modes can only exist in cavities with broken timereversal and space inversion symmetries. Their lasing frequency coincides with a spectral stationary inflection point of the underlying passive structure and is virtually independent of its size. These unidirectional lasers can be indispensable components of photonic integrated circuitry.

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The Sluggs Survey: New Evidence For A Tidal Interaction Between The Early Type Galaxies Ngc 4365 And Ngc 4342, C. Blom, D. Forbes, C. Foster, Aaron Romanowsky, J. Brodie

Faculty Research, Scholarly, and Creative Activity

We present new imaging and spectral data for globular clusters (GCs) around NGC 4365 and NGC 4342. NGC 4342 is a compact, X-ray luminous S0 galaxy with an unusually massive central black hole. NGC 4365 is another atypical galaxy that dominates the W' group of which NGC 4342 is a member. Using imaging from the MegaCam instrument on the Canada-France-Hawaii Telescope (CFHT) we identify a stream of GCs between the two galaxies and extending beyond NGC 4342. The stream of GCs is spatially coincident with a stream/plume of stars previously identified. We find that the photometric colours of the stream …

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Neutral Pion Cross Section And Spin Asymmetries At Intermediate Pseudorapidity In Polarized Proton Collisions At √ S = 200 Gev, L. Adamczyk, J. K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, S. Bültmann, I. Koralt, D. Plyku, Star Collaboration

Physics Faculty Publications

The differential cross section and spin asymmetries for neutral pions produced within the intermediate pseudorapidity range 0.8<η/c and is found to agree with a next-to-leading order perturbative QCD calculation. The longitudinal double-spin asymmetry A_LL is measured in the same pseudorapidity range and spans a range of Bjorken-x down to x≈0.01. The measured A_LL is consistent with model predictions for varying degrees of gluon polarization. The parity-violating asymmetry A_L is also measured and found to be consistent with zero. The transverse single-spin asymmetry AN is measured over a previously unexplored kinematic range in Feynman-x and P_T. Such measurements may aid our understanding of the onset and kinematic dependence of the large asymmetries observed …

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The Sluggs Survey: Breaking Degeneracies Between Dark Matter, Anisotropy And The Imf Using Globular Cluster Subpopulations In The Giant Elliptical Ngc 5846, N. Napolitano, V. Pota, Aaron Romanowsky, D. Forbes, J. Brodie, C. Foster

Faculty Research, Scholarly, and Creative Activity

We study the mass and anisotropy distribution of the giant elliptical galaxy NGC 5846 using stars, as well as the red and blue globular cluster (GC) subpopulations. We break degeneracies in the dynamical models by taking advantage of the different phase space distributions of the two GC subpopulations to unambiguously constrain the mass of the galaxy and the anisotropy of the GC system. Red GCs show the same spatial distribution and behaviour as the starlight, whereas blue GCs have a shallower density profile, a larger velocity dispersion and a lower kurtosis, all of which suggest a different orbital distribution. We …

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Dynamical Models Of Elliptical Galaxies – Ii. M87 And Its Globular Clusters, A. Angello, N. Evans, Aaron Romanowsky, J. Brodie

Faculty Research, Scholarly, and Creative Activity

We study the Globular Cluster (GC) system of the nearby elliptical galaxy M87 using the newly available dataset with accurate kinematics (Strader et al.2011). We find evidence for three distinct sub-populations of GCs in terms of colours, kinematics and radial profiles. We show that a decomposition into three populations (blue, intermediate and red GCs) is statistically preferred to one with two or four populations, and relate them to the stellar profile. We exploit the sub-populations to derive dynamical constraints on the mass and Dark Matter (DM) content of M87 out to ∼100 kpc. We use a class of global mass-estimators …

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Ultra Compact Dwarfs In The Core Of The Perseus Cluster: Ucd Formation Via Tidal Stripping, S. Penny, D. Forbes, J. Strader, C. Usher, J. Brodie, Aaron Romanowsky

Faculty Research, Scholarly, and Creative Activity

We present the results of a Keck/DEIMOS survey of Ultra Compact Dwarfs (UCDs) in the Perseus Cluster core. We confirm cluster membership for 14 UCDs, with radial velocities ~5300 km s−1. Two of these confirmed Perseus UCDs have extremely blue colours (B−R<0.6 mag), reside in star forming filaments surrounding NGC 1275, and have likely formed as massive star clusters in the last ~100 Myr. We also measure a central velocity dispersion of a third, UCD13 (σ0=38±8 km s−1), the most extended UCD in our sample. We determine it to have radius Re=85±1.1 pc, a dynamical mass of (2.3±0.8)×108 M⊙, and a metallicity [Z/H]=−0.52+0.33−0.29 dex. UCD13 and the cluster's central galaxy, NGC 1275, have a projected separation of 30 kpc and a radial velocity difference of ~20 km s−1. Based on its size, red colour, internal velocity dispersion, dynamical mass, metallicity and proximity to NGC 1275, we argue that UCD13 is likely the remnant nucleus of a tidally stripped dE, with this progenitor dE having MB≈−16 mag and mass ∼109 M⊙.

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Extended Warm Gas In The Ulirg Mrk273: Galactic Outflows And Tidal Debris, Javier Rodríguez Zaurín, Clive N. Tadhunter, David S.N. Rupke, Sylvain Veilleux, Henrik W.W. Spoon, Marco Chiaberge, Cristina Ramos Almeida, Dan Batcheldor, William B. Sparks

Aerospace, Physics, and Space Science Faculty Publications

We present new HST/ACS medium-and narrow-band images and optical Isaac Newton Telescope long-slit spectra of the merging system Mrk273. The HST observations sample the [OIII]λλ4959,5007 emission from the galaxy and the nearby continuum. These data were taken as a part of a larger study of ultraluminous infrared galaxies (ULIRGs) with the aim of investigating the importance of the warm, AGN induced outflows in such objects. The HST images show that the morphologies of the extended continuum and the ionised gas emission from the galaxy are decoupled, extending almost perpendicular to each other. In particular, we detect for the first time …

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Arrakis: Atlas Of Resonance Rings As Known In The S⁴G, Sébastien Comerón, Trisha Mizusawa

Aerospace, Physics, and Space Science Faculty Publications

Context. Resonance rings and pseudorings (here collectively called rings) are thought to be related to the gathering of material near dynamical resonances caused by non-axisymmetries in galaxy discs. This means that they are the result of secular evolution processes that redistribute material and angular momentum in discs. Studying them may give clues on the formation and growth of bars and other disc non-axisymmetries. Aims. Our aims are to produce a catalogue and an atlas of the rings detected in the Spitzer Survey of Stellar Structure in Galaxies (S⁴G) and to conduct a statistical study of the data in the catalogue. …

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Emission Lines Properties Of The Radio-Loud Quasar Lamost J1131+3114, Zhixin Shi, Georges Comte, Ali L. Luo, Tuehong H. Zhao, Jingkun K. Zhao, T D. Oswalt, Fuchao C. Wu

Aerospace, Physics, and Space Science Faculty Publications

The radio-loud quasar LAMOST J1131+3114 (Ton 580, B2 1128+315), showing asymmetrical profile in Hβ and [O III] lines, has been selected from the LAMOST Pilot Survey for further study. We present an analysis of its emission lines by means of multiple Gaussian fitting, performed on LAMOST, Apache Point Observatory, and archival spectra. The broad line region, with an Hβ line of FWHM ~ 4000 km sˉ¹ has been fit with a double Gaussian, one of which is very broad and redshifted from the reference frame. The object is a likely Population B quasar. The [O III] λλ4959,5007 lines profiles of …

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Modulated X-Ray Emission Of The Magnetic O8.5v-Star Tr16-22, Yaël Nazé, Gregg A. Wade, Véronique Petit

Aerospace, Physics, and Space Science Faculty Publications

Using an extensive X-ray dataset, we analyzed the X-ray emission of the massive O-star Tr16-22, which was recently found to be magnetic. Its bright X-ray emission is found to be modulated with a 54d period. This timescale should represent the rotational timescale of the star, as it does for other magnetic massive stars. In parallel, new spectropolarimetric data confirm the published magnetic detection.

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Embedded Star Formation In S4g Galaxy Dust Lanes, Debra M. Elmegreen, Trisha Mizusawa

Aerospace, Physics, and Space Science Faculty Publications

Star-forming regions that are visible at 3.6 μm and Hα but not in the u, g, r, i, z bands of the Sloan Digital Sky Survey are measured in five nearby spiral galaxies to find extinctions averaging ∼3.8 mag and stellar masses averaging ∼5 × 104 M ⊙. These regions are apparently young star complexes embedded in dark filamentary shock fronts connected with spiral arms. The associated cloud masses are ∼10 7 M ⊙. The conditions required to make such complexes are explored, including gravitational instabilities in spiral-shocked gas and compression of incident clouds. We find that instabilities are too …

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An Analytical Approach For Calculating Energy Spectra Of Relativistic Runaway Electron Avalanches In Air, Eric S. Crame, Joseph R. Dwyer, Shahab Arabshahi, Igor B. Vodopiyanov, Ningyu Liu, Hamid K. Rassoul

Aerospace, Physics, and Space Science Faculty Publications

Simplified equations describing the transport and energy spectrum of runaway electrons are derived from the basic kinematics of the continuity equations. These equations are useful in modeling the energy distribution of energetic electrons in strong electric fields, such as those found inside thunderstorms. Dwyer and Babich (2011) investigated the generation of low-energy electrons in relativistic runaway electron avalanches. The paper also developed simple analytical expressions to describe the detailed physics of Monte Carlo simulations of relativistic runaway electrons in air. In the current work, the energy spectra of the runaway electron population are studied in detail. Dependence of electron avalanche …

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Proceedings Of The First International Conference On Superluminal Physics & Instantaneous Physics As New Fields Of Research, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In a similar way as passing from Euclidean Geometry to Non-Euclidean Geometry, we can pass from Subluminal Physics to Superluminal Physics, and further to Instantaneous Physics (instantaneous traveling). In the lights of two consecutive successful CERN experiments with superluminal particles in the fall of 2011, we believe these two new fields of research should begin developing. A physical law has a form in Newtonian physics, another form in the Relativity Theory, and different form at Superluminal theory, or at Instantaneous (infinite) speeds – according to the S-Denying Theory spectrum. First, we extend physical laws and formulas to superluminal traveling and …

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Neutrosophic Theory And Its Applications : Collected Papers - Vol. 1, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Neutrosophic Theory means Neutrosophy applied in many fields in order to solve problems related to indeterminacy. Neutrosophy is a new branch of philosophy that studies the origin, nature, and scope of neutralities, as well as their interactions with different ideational spectra. This theory considers every entity together with its opposite or negation and with their spectrum of neutralities in between them (i.e. entities supporting neither nor ). The and ideas together are referred to as . Neutrosophy is a generalization of Hegel's dialectics (the last one is based on and only). According to this theory every entity tends to be …

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Astrophysics and Astronomy Commons^™

Full-Text Articles in Astrophysics and Astronomy

Unidirectional Lasing Emerging From Frozen Light In Nonreciprocal Cavities, Hamidreza Ramezani, S. Kalish, I. Vitebskiy, T. Kottos

Physics & Astronomy Faculty Publications

The Sluggs Survey: New Evidence For A Tidal Interaction Between The Early Type Galaxies Ngc 4365 And Ngc 4342, C. Blom, D. Forbes, C. Foster, Aaron Romanowsky, J. Brodie

Faculty Research, Scholarly, and Creative Activity

Neutral Pion Cross Section And Spin Asymmetries At Intermediate Pseudorapidity In Polarized Proton Collisions At √ S = 200 Gev, L. Adamczyk, J. K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, S. Bültmann, I. Koralt, D. Plyku, Star Collaboration

Physics Faculty Publications

The Sluggs Survey: Breaking Degeneracies Between Dark Matter, Anisotropy And The Imf Using Globular Cluster Subpopulations In The Giant Elliptical Ngc 5846, N. Napolitano, V. Pota, Aaron Romanowsky, D. Forbes, J. Brodie, C. Foster

Faculty Research, Scholarly, and Creative Activity

Dynamical Models Of Elliptical Galaxies – Ii. M87 And Its Globular Clusters, A. Angello, N. Evans, Aaron Romanowsky, J. Brodie

Faculty Research, Scholarly, and Creative Activity

Ultra Compact Dwarfs In The Core Of The Perseus Cluster: Ucd Formation Via Tidal Stripping, S. Penny, D. Forbes, J. Strader, C. Usher, J. Brodie, Aaron Romanowsky

Faculty Research, Scholarly, and Creative Activity

Extended Warm Gas In The Ulirg Mrk273: Galactic Outflows And Tidal Debris, Javier Rodríguez Zaurín, Clive N. Tadhunter, David S.N. Rupke, Sylvain Veilleux, Henrik W.W. Spoon, Marco Chiaberge, Cristina Ramos Almeida, Dan Batcheldor, William B. Sparks

Aerospace, Physics, and Space Science Faculty Publications

Arrakis: Atlas Of Resonance Rings As Known In The S⁴G, Sébastien Comerón, Trisha Mizusawa

Aerospace, Physics, and Space Science Faculty Publications

Emission Lines Properties Of The Radio-Loud Quasar Lamost J1131+3114, Zhixin Shi, Georges Comte, Ali L. Luo, Tuehong H. Zhao, Jingkun K. Zhao, T D. Oswalt, Fuchao C. Wu

Aerospace, Physics, and Space Science Faculty Publications

Modulated X-Ray Emission Of The Magnetic O8.5v-Star Tr16-22, Yaël Nazé, Gregg A. Wade, Véronique Petit

Aerospace, Physics, and Space Science Faculty Publications

Embedded Star Formation In S4g Galaxy Dust Lanes, Debra M. Elmegreen, Trisha Mizusawa

Aerospace, Physics, and Space Science Faculty Publications

An Analytical Approach For Calculating Energy Spectra Of Relativistic Runaway Electron Avalanches In Air, Eric S. Crame, Joseph R. Dwyer, Shahab Arabshahi, Igor B. Vodopiyanov, Ningyu Liu, Hamid K. Rassoul

Aerospace, Physics, and Space Science Faculty Publications

Proceedings Of The First International Conference On Superluminal Physics & Instantaneous Physics As New Fields Of Research, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Neutrosophic Theory And Its Applications : Collected Papers - Vol. 1, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications