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Astrophysics and Astronomy

2001

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Articles 1 - 30 of 137

Full-Text Articles in Physical Sciences and Mathematics

Origins Of Nonstoichiometry And Vacancy Ordering In Sc1-X□Xs, Gus L. W. Hart, Alex Zunger Dec 2001

Origins Of Nonstoichiometry And Vacancy Ordering In Sc1-X□Xs, Gus L. W. Hart, Alex Zunger

Faculty Publications

Whereas nearly all compounds AnBm obey Dalton's rule of integer stoichiometry (n:m, both integer), there is a class of systems, exemplified by the rocksalt structure Sc1-x□xS, that exhibits large deviations from stoichiometry via vacancies, even at low temperatures. By combining first-principles total energy calculations with lattice statistical mechanics, we scan an astronomical number of possible structures, identifying the stable ground states. Surprisingly, all have the same motifs: (111) planes with (112) vacancy rows arranged in (110) columns. Electronic structure calculations of the ground states (identified out of ~3 × 10^6 structures) reveal the remarkable origins of nonstoichiometry.

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Isotopic Composition Of Solar Energetic Particle Events Measured By Advanced Composition Explorer/Uleis, Joseph R. Dwyer, Glenn M. Mason, Joseph E. Mazur, Robert E. Gold, Stamatios M. Krimigis, Eberhard S. Möbius, Mark A. Popecki Dec 2001

Isotopic Composition Of Solar Energetic Particle Events Measured By Advanced Composition Explorer/Uleis, Joseph R. Dwyer, Glenn M. Mason, Joseph E. Mazur, Robert E. Gold, Stamatios M. Krimigis, Eberhard S. Möbius, Mark A. Popecki

Aerospace, Physics, and Space Science Faculty Publications

Since its 1997 August launch, the Ultra Low Energy Isotope Spectrometer (ULEIS) on board the Advanced Composition Explorer (ACE) has observed a large number of solar energetic particle (SEP) events in the 0.4-3 MeV nucleonˉ¹ range. These events show remarkable variability of both the elemental and isotopic compositions, with ²²Ne/²⁰Ne varying, from event to event, by up to a factor of 10, Fe/O by up to a factor of 100, and ³He/⁴He by up to a factor of 104. In this paper we present new measurements of the ²²Ne/²⁰Ne, ²⁶Mg/²⁴Mg, and ³He/⁴He ratios at ∼ 1 MeV nucleonˉ¹ and compare …

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Ccd Photometry Of The Classic Second-Parameter Globular Clusters M3 And M13, Soo-Chang Rey, Suk-Jin Yoon, Young-Wook Lee, Brian Chaboyer, Ata Sarajedini Dec 2001

Ccd Photometry Of The Classic Second-Parameter Globular Clusters M3 And M13, Soo-Chang Rey, Suk-Jin Yoon, Young-Wook Lee, Brian Chaboyer, Ata Sarajedini

Dartmouth Scholarship

We present high-precision V, B-V color-magnitude diagrams (CMDs) for the classic second-parameter globular clusters M3 and M13 from wide-field, deep CCD photometry. The data for the two clusters were obtained during the same photometric nights with the same instrument, allowing us to determine accurate relative ages. Based on a differential comparison of the CMDs using the Δ(B-V) method, an age difference of 1.7 ± 0.7 Gyr is obtained between these two clusters. We compare this result with our updated horizontal-branch (HB) population models, which confirm that the observed age difference can produce the …

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Chromospherically Active Stars. Xx. The Giant Single-Lined Binary Hd 161570, Francis C. Fekel, Gregory W. Henry, Stephen M. Henry Dec 2001

Chromospherically Active Stars. Xx. The Giant Single-Lined Binary Hd 161570, Francis C. Fekel, Gregory W. Henry, Stephen M. Henry

Information Systems and Engineering Management Research Publications

Spectroscopy of HD 161570 shows it to be a single-lined spectroscopic binary with a period of 45.623 days and a nearly circular orbit. The primary star has spectral type G7 III, and the secondary is most likely a G or K dwarf. A high-resolution spectrum of the 3950 Å region confirms that the primary has Ca II H and K emission lines. The logarithm of the giant's lithium abundance is less than 0.9, indicating that it is not lithium-rich. From photometric observations covering six seasons, we detected periodic short-term light variability with an amplitude ranging from 0.02 to 0.04 mag. …

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A New System Of Parallel Isolated Nonthermal Filaments Near The Galactic Center: Evidence For A Local Magnetic Field Gradient, Ted N. La Rosa, Joseph W. Lazio, Nasir E. Kassim Dec 2001

A New System Of Parallel Isolated Nonthermal Filaments Near The Galactic Center: Evidence For A Local Magnetic Field Gradient, Ted N. La Rosa, Joseph W. Lazio, Nasir E. Kassim

Faculty and Research Publications

We report the discovery of a system of isolated nonthermal filaments approximately 0fdg5 northwest (75 pc in projection) of Sgr A. Unlike other isolated nonthermal filaments which show subfilamentation, braiding of subfilaments, and flaring at their ends, these filaments are simple linear structures and more closely resemble the parallel bundled filaments in the Galactic center radio arc. However, the most unusual feature of these filaments is that the 20/90 cm spectral index uniformly decreases as a function of length, in contrast to all other nonthermal filaments in the Galactic center. This spectral gradient may not be due to simple particle …

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Fine-Tuning Solution For Hybrid Inflation In Dissipative Chaotic Dynamics, Rudnei O. Ramos Nov 2001

Fine-Tuning Solution For Hybrid Inflation In Dissipative Chaotic Dynamics, Rudnei O. Ramos

Dartmouth Scholarship

We study the presence of chaotic behavior in phase space in the preinflationary stage of hybrid inflation models. This is closely related to the problem of initial conditions associated with these inflationary types of model. We then show how an expected dissipative dynamics of fields just before the onset of inflation can solve or ease considerably the problem of initial conditions, driving the system naturally toward inflation. The chaotic behavior of the corresponding dynamical system is studied by computation of the fractal dimension of the boundary in phase space separating inflationary from noninflationary trajectories. The fractal dimension for this boundary …

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Three-Dimensional Spectral Classification Of Low-Metallicity Stars Using Artificial Neural Networks, Shawn Snider, Ted Von Hippel, Et Al. Nov 2001

Three-Dimensional Spectral Classification Of Low-Metallicity Stars Using Artificial Neural Networks, Shawn Snider, Ted Von Hippel, Et Al.

Publications

We explore the application of artificial neural networks (ANNs) for the estimation of atmospheric parameters (Teff, log g, and [Fe/H]) for Galactic F- and G-type stars. The ANNs are fed with medium-resolution (Δλ ~ 1-2 Å) non-flux-calibrated spectroscopic observations. From a sample of 279 stars with previous high-resolution determinations of metallicity and a set of (external) estimates of temperature and surface gravity, our ANNs are able to predict Teff with an accuracy of σ(Teff) = 135-150 K over the range 4250 ≤ Teff ≤ 6500 K, log g with an accuracy …

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No Planet For Hd 166435, Didier Queloz, Gregory W. Henry, Jean-Pierre Sivan, Sallie L. Baliunas, Jean-Luc Beuzit, Robert A. Donahue, Michel Mayor, Dominique Naef, Christian Perrier, Stephane Udry Nov 2001

No Planet For Hd 166435, Didier Queloz, Gregory W. Henry, Jean-Pierre Sivan, Sallie L. Baliunas, Jean-Luc Beuzit, Robert A. Donahue, Michel Mayor, Dominique Naef, Christian Perrier, Stephane Udry

Information Systems and Engineering Management Research Publications

The G0 V star HD 166435 has been observed by the fiber-fed spectrograph ELODIE as one of the targets in the large extra-solar planet survey that we are conducting at the Observatory of Haute-Provence. We detected coherent, low-amplitude, radial-velocity variations with a period of 3.7987 days, suggesting a possible close-in planetary companion. Subsequently, we initiated a series of high-precision photometric observations to search for possible planetary transits and an additional series of Ca II H and K observations to measure the level of surface magnetic activity and to look for possible rotational modulation. Surprisingly, we found the star to be …

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Entropy Splitting For High Order Numerical Simulation Of Vortex Sound At Low Mach Numbers, Bernhard Müller, H. C. Yee Nov 2001

Entropy Splitting For High Order Numerical Simulation Of Vortex Sound At Low Mach Numbers, Bernhard Müller, H. C. Yee

United States National Aeronautics and Space Administration: Publications

Several recent developments in efficient, stable, highly parallelizable high order non-dissipative spatial schemes with characteristic based filters that exhibit low dissipation for long time linear and nonlinear wave propagations are utilized for computational aeroacoustics (CAA). For stability consideration, the Euler equations are split into a conservative and a symmetric non-conservative portion. Due to the large disparity of acoustic and stagnation quantities in low Mach number aeroacoustics, the split Euler equations are formulated in perturbation form to minimize numerical cancellation errors. Spurious oscillations are suppressed by a characteristic-based filter. The method has been applied to accurately simulate the sound emitted by …

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Hubble Space Telescope Wfpc2 Imaging Of Cassiopeia A, R. A. Fesen, J. A. Morse, R. A. Chevalier, K. J. Borkowski, C. L. Gerardy Nov 2001

Hubble Space Telescope Wfpc2 Imaging Of Cassiopeia A, R. A. Fesen, J. A. Morse, R. A. Chevalier, K. J. Borkowski, C. L. Gerardy

Dartmouth Scholarship

The young galactic supernova remnant Cassiopeia A was imaged with Wide Field Planetary Camera 2 (WFPC2) aboard the Hubble Space Telescope through filters selected to capture the complete velocity range of the remnant's main shell in several emission lines. The primary lines detected, along with the specific WFPC2 filters used, were [O III] λλ4959, 5007 (F450W), [N II] λ6583 (F658N), [S II] λλ6716, 6731 + [O II] λλ7319, 7330 + [O I] λλ6300, 6364 (F675W), and [S III] λλ9069, 9532 (F850LP). About three-quarters of the remnant's 4' diameter main shell was imaged with all four filters in three WFPC2 pointings, …

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Comparison Of Stellar Angular Diameters From The Npoi, The Mark Iii Optical Interferometer, And The Infrared Flux Method, Tyler E. Nordgren, Jeffrey J. Sudol, D. Mozurkewich Nov 2001

Comparison Of Stellar Angular Diameters From The Npoi, The Mark Iii Optical Interferometer, And The Infrared Flux Method, Tyler E. Nordgren, Jeffrey J. Sudol, D. Mozurkewich

Physics & Engineering Faculty Publications

No abstract provided.

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A Robotic Wide-Angle Hα Survey Of The Southern Sky, John E. Gaustad, P. R. Mccullough, W. Rosing, D. Van Buren Nov 2001

A Robotic Wide-Angle Hα Survey Of The Southern Sky, John E. Gaustad, P. R. Mccullough, W. Rosing, D. Van Buren

Physics & Astronomy Faculty Works

We have completed a robotic wide-angle imaging survey of the southern sky (delta = +15 degrees to -90 degrees) at 656.3 nm wavelength, the H alpha emission line of hydrogen. Each image of the resulting Southern H alpha Sky Survey Atlas (SHASSA) covers an area of the sky 13 degrees square at an angular resolution of approximately 0.'8 and reaches a sensitivity level of 2 R (1.2 x 10(-17) ergs cm(-2) s(-1) arcsec(-2)) pixel(-1), corresponding to an emission measure of 4 cm(-6) pc and to a brightness temperature for microwave free-free emission of 12 muK at 30 GHz. Smoothing over …

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Investigating The Long-Term Evolution Of Galaxies: Noise, Cuspy Halos And Bars, Martin D. Weinberg Oct 2001

Investigating The Long-Term Evolution Of Galaxies: Noise, Cuspy Halos And Bars, Martin D. Weinberg

Astronomy Department Faculty Publication Series

I review the arguments for the importance of halo structure in driving galaxy evolution and coupling a galaxy to its environment. We begin with a general discussion of the key dynamics and examples of structure dominated by modes. We find that simulations with large numbers of particles (N ≥ 106) are required to resolve the dynamics. Finally, I will describe some new results which demonstrates that a disk bar can produce cores in a cuspy CDM dark-matter profile within a gigayear. An inner Lindblad-like resonance couples the rotating bar to halo orbits at all radii through the cusp, rapidly flattening …

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The Planetary Nebula A39: An Observational Benchmark For Numerical Modeling Of Photoionized Plasmas, George H. Jacoby, Gary J. Ferland, Kirk T. Korista Oct 2001

The Planetary Nebula A39: An Observational Benchmark For Numerical Modeling Of Photoionized Plasmas, George H. Jacoby, Gary J. Ferland, Kirk T. Korista

Physics and Astronomy Faculty Publications

Galactic nebulae are the main probes for the chemical evolution of the interstellar medium. Yet, recent observations have shown that chemical abundances determined from recombination and collisionally excited emission lines can differ by as much as an order of magnitude in some planetary nebulae (PNs). Many PNs have complex geometries and morphological evidence for interactions from stellar winds, and it is not clear to what extent winds, inhomogeneities, or shocked gas affect the observed spectrum. There currently is no full explanation for this discrepancy, which brings into question whether we understand the physical state of these low-density plasmas at all. …

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The Cataclysmic Variable Cw 1045+525: A Secondary-Dominated Dwarf Nova?, C. Tappert, J. R. Thorstensen, W. H. Fenton, N. Bennert Oct 2001

The Cataclysmic Variable Cw 1045+525: A Secondary-Dominated Dwarf Nova?, C. Tappert, J. R. Thorstensen, W. H. Fenton, N. Bennert

Dartmouth Scholarship

We present spectroscopic and photometric observations of the cataclysmic variable CW 1045+525. Both the optical spectrum and the photometric lightcurve show a strong contribution of a K5V–M0V secondary. We derive an orbital period Porb = 0.271278(1) d by measuring the radial velocities of the absorption lines of the secondary. The period and spectral type of the secondary suggest a distance of 350–700 pc. There is evidence for additional sources of line- and continuum emission, but no direct evidence of an accretion disc. We discuss several scenarios for the nature of CW 1045+525 on the basis of our results, finding a …

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Statistics And Supermetallicity: The Metallicity Of Mu Leonis, B. J. Taylor Oct 2001

Statistics And Supermetallicity: The Metallicity Of Mu Leonis, B. J. Taylor

Faculty Publications

For the often-studied "SMR" giant µ Leo, Smith & Ruck (2000) have recently found that [Fe/H] approximately + 0.3 dex. Their conclusion is tested here in a "statistical" paradigm, in which statistical principles are used to select published high-dispersion µ Leo data and assign error bars to them. When data from Smith & Ruck and from Takeda et al. (1998) are added to a data base compiled in 1999, it is found that conclusions from an earlier analysis (Taylor 1999c) are essentially unchanged: the mean value of [Fe/H] approximately + 0.23 ± 0.025 dex, and values ≤ + 0.2 dex …

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Cross Sections Fall 2001, Department Of Physics And Astronomy Oct 2001

Cross Sections Fall 2001, Department Of Physics And Astronomy

Cross Sections

No abstract provided.

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Spectroscopy And Orbital Periods Of Four Cataclysmic Variable Stars, John R. Thorstensen, Cynthia J. Taylor Oct 2001

Spectroscopy And Orbital Periods Of Four Cataclysmic Variable Stars, John R. Thorstensen, Cynthia J. Taylor

Dartmouth Scholarship

We present spectroscopy and orbital periods Porb of four relatively little-studied cataclysmic variable stars. The stars and their periods are: AF Cam, Porb = 0.324(1) d (the daily cycle count is slightly ambiguous); V2069 Cyg (= RX J2123.7+4217), 0.311683(2) d; PG 0935+075, 0.1868(3) d; and KUV 03580+0614, 0.1495(6) d. V2069 Cyg and KUV 03580+0614 both show He iiλ4686 emission comparable in strength to Hβ. V2069 Cyg appears to be a luminous nova-like variable, and the strong He ii suggests it may be an intermediate polar. The period of KUV 03580+0614 is similar to members …

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Multiwavelength Observations Of A Tev-Flare From W Comae, P. T. Reynolds, Veritas, Agile Oct 2001

Multiwavelength Observations Of A Tev-Flare From W Comae, P. T. Reynolds, Veritas, Agile

Physical Sciences Publications

No abstract provided.

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X-Ray Line Profiles From Parameterized Emission Within An Accelerating Stellar Wind, S. P. Owocki, David H. Cohen Oct 2001

X-Ray Line Profiles From Parameterized Emission Within An Accelerating Stellar Wind, S. P. Owocki, David H. Cohen

Physics & Astronomy Faculty Works

Motivated by recent detections by the XMM and Chandra satellites of X-ray line emission from hot, luminous stars, we present synthetic line profiles for X-rays emitted within parameterized models of a hot-star wind. The X-ray line emission is taken to occur at a sharply defined comoving-frame resonance wavelength, which is Doppler-shifted by a stellar wind outflow parameterized by a "beta" velocity law, nu (r) = nu (infinity)(1-R-*/r)(beta). Above some initial onset radius for R-o X-ray emission, the radial variation of the emission filling factor is assumed to decline as a power law in radius, f (r) similar tor(-q). The computed …

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Spectral Energy Distribution Signatures Of Jovian Planets Around White Dwarf Stars., R. Ignace Sep 2001

Spectral Energy Distribution Signatures Of Jovian Planets Around White Dwarf Stars., R. Ignace

Richard Ignace

The problem of detecting Jovian-sized planets orbiting white dwarf stars is considered. Significant IR excesses result from warm Jupiters orbiting a white dwarf of Teff = 10,000 K at a distance of ~103 white dwarf radii (corresponding to ~102 Jupiter radii or a few tenths of an AU) with an orbital period of ~100 days. Such a planet will have a 10 µm flux density at its Wien peak that is comparable to the emission of the white dwarf at that wavelength. Although the white dwarf is much hotter than the planet, the planet will have peak …

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Chemical Bonding, Elasticity, And Valence Force Field Models: A Case Study For Α-Pt2si And Ptsi, Gus L. W. Hart, J. E. Klepeis, O. Beckstein, O. Pankratov Sep 2001

Chemical Bonding, Elasticity, And Valence Force Field Models: A Case Study For Α-Pt2si And Ptsi, Gus L. W. Hart, J. E. Klepeis, O. Beckstein, O. Pankratov

Faculty Publications

We have carried out a detailed study of the chemical bonding for two room-temperature stable platinum silicide phases, tetragonal α-Pt2Si. These elements of the bonding are further analyzed by constructing valence force field models using the results from recent first principles calculations of the six (nine) independent, nonzero elastic constants of α-Pt2Si (PtSi). The resulting volume-, radial-, and angular-dependent force constants provide insight into the relative strength of various bonding elements as well as the trends observed in the elastic constants themselves. The valence force field analysis yields quantitative information about the nature of the chemical bonding that is not …

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Poynting's Theorem And Luminal Total Energy Transport In Passive Dielectric Media, Scott Glasgow, Michael Ware, Justin Peatross Sep 2001

Poynting's Theorem And Luminal Total Energy Transport In Passive Dielectric Media, Scott Glasgow, Michael Ware, Justin Peatross

Faculty Publications

Without approximation the energy density in Poynting's theorem for the generally dispersive and passive dielectric medium is demonstrated to be a system total dynamical energy density. Thus the density in Poynting's theorem is a conserved form that by virtue of its positive definiteness prescribes important qualitative and quantitative features of the medium-field dynamics by rendering the system dynamically closed. This fully three-dimensional result, applicable to anisotropic and inhomogeneous media, is model independent, relying solely on the complex-analytic consequences of causality and passivity. As direct applications of this result, we show 1 that a causal medium responds to a virtual, instantaneous …

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Comparing The Sfi Peculiar Velocities With The Pscz Gravity Field: A Velmod Analysis, E. Branchini, W. Freudling, L. N. Da Costa, C. S. Frenk, R. Giovanelli, M. P. Haynes, J. J. Salzer, G. Wegner, I. Zehavi Sep 2001

Comparing The Sfi Peculiar Velocities With The Pscz Gravity Field: A Velmod Analysis, E. Branchini, W. Freudling, L. N. Da Costa, C. S. Frenk, R. Giovanelli, M. P. Haynes, J. J. Salzer, G. Wegner, I. Zehavi

Dartmouth Scholarship

We compare the peculiar velocities derived from the I-band Tully–Fisher (TF) relation for 989 field spiral galaxies in the SFI catalogue with the predicted velocity field derived from the IRAS PSCz galaxy redshift survey. We assume linear gravitational instability theory and apply the maximum likelihood technique, VELMOD to SFI galaxies within a redshift cz LG =6000 km s−1. The resulting calibration of the TF relation is consistent with a previous, independent calibration for a similar sample of spirals residing in clusters. Our analysis provides an accurate estimate of the quantity βI ≡ Ωm0.6 …

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Plasma Transport At The Magnetospheric Boundary Due To Reconnection In Kelvin-Helmholtz Vortices, K. Nykyri, A. Otto Sep 2001

Plasma Transport At The Magnetospheric Boundary Due To Reconnection In Kelvin-Helmholtz Vortices, K. Nykyri, A. Otto

Publications

The Kelvin-Helmholtz( KH) mode has long been considered for viscous interaction at the magnetospheric boundary but it is not expected to produce significant mass transport. The presented results indicate that the Kelvin- Helmholtz instability can indeed cause a transfer of mass into the magnetotail during times of northward IMF. The vortex motion of KH waves can generate a strongly twisted magnetic field with multiple current layers. Magnetic reconnection in the strong current layers inside the vortices can detach high density plasma filaments from the magnetosheath. This may explain observed high density and low temperature filaments in the magnetosphere and the …

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Line Forces In Keplerian Circumstellar Disks And Precession Of Nearly Circular Orbits., K. G. Gayley, R. Ignace, S. P. Owocki Sep 2001

Line Forces In Keplerian Circumstellar Disks And Precession Of Nearly Circular Orbits., K. G. Gayley, R. Ignace, S. P. Owocki

Richard Ignace

We examine the effects of optically thick line forces on orbiting circumstellar disks, such as occur around Be stars. For radially streaming radiation, line forces are only effective if there is a strong radial velocity gradient, as occurs, for example, in a line-driven stellar wind. However, within an orbiting disk, the radial shear of the azimuthal velocity leads to strong line-of-sight velocity velocity gradients along nonradial directions. As such, in the proximity of a stellar surface extending over a substantial cone angle, the nonradial stellar radiation can impart a significant line force, even in the case of purely circular orbits. …

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Terminal Speeds And Ion Fractions From [Caiv] 3.207 Μm In Three Single Wn Stars., Richard Ignace Sep 2001

Terminal Speeds And Ion Fractions From [Caiv] 3.207 Μm In Three Single Wn Stars., Richard Ignace

Richard Ignace

We report on the forbidden emission lines of [CaIV] at 3.207 μm and [NeIII] at 15.56 μm based on Infrared Space Observatory observations. The data set consists of three single Wolf-Rayet stars (WR 1, WR 134, and WR 136) and three binary systems (WR 11, WR 146, and WR 147). For the single stars, only the [CaIV] line was observed. Our primary objectives are to determine the wind terminal speed from the emission-line widths, derive ion number fractions, and discuss the relation between emission profile shapes and wind flow geometry. Compared to previous determinations of the terminal speed, we find …

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Large-Scale Power Spectrum And Structures From The Enear Galaxy Peculiar Velocity Catalogue, S. Zaroubi, M. Bernardi, L. N. Da Costa, Y. Hoffman, M. V. Alonso, G. Wegner Sep 2001

Large-Scale Power Spectrum And Structures From The Enear Galaxy Peculiar Velocity Catalogue, S. Zaroubi, M. Bernardi, L. N. Da Costa, Y. Hoffman, M. V. Alonso, G. Wegner

Dartmouth Scholarship

We estimate the mass density fluctuations power spectrum (PS) on large scales by applying a maximum likelihood technique to the peculiar velocity data of the recently completed redshift—distance survey of early-type galaxies (hereafter ENEAR). Parametric cold dark matter (CDM)-like models for the PS are assumed, and the best-fitting parameters are determined by maximizing the probability of the model given the measured peculiar velocities of the galaxies, their distances and estimated errors. The method has been applied to CDM models with and without COBE normalization. The general results are in agreement with the high-amplitude power spectra found from similar analyses of …

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The First Detection Of Coherent Emission From Radio Pulsars, F. A. Jenet, S. B. Anderson, T. A. Prince Sep 2001

The First Detection Of Coherent Emission From Radio Pulsars, F. A. Jenet, S. B. Anderson, T. A. Prince

Physics and Astronomy Faculty Publications and Presentations

The statistical properties of the radio emission from the pulsars B0823+26, B0950+08, B1133+16, and B1937+21 are studied using high time resolution observations taken at the Arecibo Observatory in Puerto Rico. Temporally coherent non-Gaussian emission has been detected in three of the four observed objects. This is the first time such a phenomenon has been observed. The results have been interpreted using a generalized shot noise model, and various basic physical quantities pertaining to the magnetospheric plasma have been estimated.

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Grb 010222: A Burst Within A Starburst, D. A. Frail, F. Bertoldi, G. H. Moriarty‐Schieven, E. Berger, P. A. Price, J. S. Bloom, R. Sari, S. R. Kulkarni, C. L. Gerardy, D. E. Reichart Aug 2001

Grb 010222: A Burst Within A Starburst, D. A. Frail, F. Bertoldi, G. H. Moriarty‐Schieven, E. Berger, P. A. Price, J. S. Bloom, R. Sari, S. R. Kulkarni, C. L. Gerardy, D. E. Reichart

Dartmouth Scholarship

We present millimeter and submillimeter wavelength observations and near-infrared K -band imaging toward the bright gamma-ray burst GRB 010222. Over seven epochs the flux density of the source was constant wit h an average flux density 3.74 ± 0.53 mJy at 350 GHz and 1.05 ± 0.22 mJy at 250 GHz, giving a spectral index α = 3 . 78 ± 0.25 (where F∝ να). We rule out the possibility that this emission originated from the burst or its afterglow and we conclu de that it is due to a dusty, high redshift starburst galaxy (SMM J14522+43 01). …

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