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Articles 1 - 11 of 11

Full-Text Articles in Physical Sciences and Mathematics

Wesleyan's Mark Evans Observatory Designated Official Site, Kim Hill Oct 2013

Wesleyan's Mark Evans Observatory Designated Official Site, Kim Hill

News and Events

No abstract provided.


Nsf Funds Study Of Cosmic Dust, Kim Hill Sep 2013

Nsf Funds Study Of Cosmic Dust, Kim Hill

News and Events

No abstract provided.


Astronomy Talk, Sherry Wallace Jun 2013

Astronomy Talk, Sherry Wallace

News and Events

No abstract provided.


Accompanying Figures For "Rotation Periods Of Small Trojan Asteroids", Linda French Jan 2013

Accompanying Figures For "Rotation Periods Of Small Trojan Asteroids", Linda French

Scholarship

No abstract provided.


Ultra-Sensitive High-Precision Spectroscopy Of A Fast Molecular Ion Beam, A. Mills, B. Stiller, M. Porambo, Manori Perera, H. Kreckel, B. Mccall Jan 2011

Ultra-Sensitive High-Precision Spectroscopy Of A Fast Molecular Ion Beam, A. Mills, B. Stiller, M. Porambo, Manori Perera, H. Kreckel, B. Mccall

Scholarship

Direct spectroscopy of a fast molecular ion beam offers many advantages over competing techniques, including the generality of the approach to any molecular ion, the complete elimination of spectral confusion due to neutral molecules, and the mass identification of individual spectral lines. The major challenge is the intrinsic weakness of absorption or dispersion signals resulting from the relatively low number density of ions in the beam. Direct spectroscopy of an ion beam was pioneered by Saykally and co-workers in the late 1980s, but has not been attempted since that time. Here, we present the design and construction of an ion …


On The Clustering Of Sub-Millimeter Galaxies, Christina Williams, Mauro Giavalisco, Cristiano Porciani, Min Yun, Alexandra Pope, Kimberly Scott, Jason Austermann, Itziar Aretxaga, Bunyo Hatsukade, Kyoung-Soo Lee, Grant Wilson, J. Ryan Cybulski, David Hughes, Ryo Kawabe, Kotaro Kohno, Thushara Perera, F. Peter Schloerb Jan 2011

On The Clustering Of Sub-Millimeter Galaxies, Christina Williams, Mauro Giavalisco, Cristiano Porciani, Min Yun, Alexandra Pope, Kimberly Scott, Jason Austermann, Itziar Aretxaga, Bunyo Hatsukade, Kyoung-Soo Lee, Grant Wilson, J. Ryan Cybulski, David Hughes, Ryo Kawabe, Kotaro Kohno, Thushara Perera, F. Peter Schloerb

Scholarship

We measure the angular two-point correlation function of sub-millimeter galaxies (SMGs) from 1.1-millimeter imaging of the COSMOS field with the AzTEC camera and ASTE 10-meter telescope. These data yields one of the largest contiguous samples of SMGs to date, covering an area of 0.72 degrees^2 down to a 1.26 mJy/beam (1-sigma) limit, including 189 (328) sources with S/N greater than 3.5 (3). We can only set upper limits to the correlation length r_0, modeling the correlation function as a power-law with pre-assigned slope. Assuming existing redshift distributions, we derive 68.3% confidence level upper limits of r_0 < 6-8 h^-1 Mpc at 3.7 mJy, and r_0 < 11-12 h^-1 Mpc at 4.2 mJy. Although consistent with most previous estimates, these upper limits imply that the real r_0 is likely smaller. This casts doubts on the robustness of claims that SMGs are characterized by significantly stronger spatial clustering, (and thus larger mass), than differently selected galaxies at high-redshift. Using Monte Carlo simulations we show that even strongly clustered distributions of galaxies can appear unclustered when sampled with limited sensitivity and coarse angular resolution common to current sub-millimeter surveys. The simulations, however, also show that unclustered distributions can appear strongly clustered under these circumstances. From the simulations, we predict that at our survey depth, a mapped area of two degrees^2 is needed to reconstruct the correlation function, assuming smaller beam sizes of future surveys (e.g. the Large Millimeter Telescope's 6" beam size). At present, robust measures of the clustering strength of bright SMGs appear to be below the reach of most observations.


Ultra-Sensitive High-Precision Spectroscopy Of A Fast Molecular Ion Beam, A. A. Mills, B. M. Stiller, M. W. Porambo, Manori Perera, H. Kreckel, B. J. Mccall Jan 2011

Ultra-Sensitive High-Precision Spectroscopy Of A Fast Molecular Ion Beam, A. A. Mills, B. M. Stiller, M. W. Porambo, Manori Perera, H. Kreckel, B. J. Mccall

Manori Perera

Direct spectroscopy of a fast molecular ion beam offers many advantages over competing techniques, including the generality of the approach to any molecular ion, the complete elimination of spectral confusion due to neutral molecules, and the mass identification of individual spectral lines. The major challenge is the intrinsic weakness of absorption or dispersion signals resulting from the relatively low number density of ions in the beam. Direct spectroscopy of an ion beam was pioneered by Saykally and co-workers in the late 1980s, but has not been attempted since that time. Here, we present the design and construction of an ion …


Origins Of The Extragalactic Background At 1mm From A Combined Analysis Of The Aztec And Mambo Data In Goods-N, Kyle Penner, Alexandra Pope, Edward Chapin, Thomas Greve, Frank Bertoldi, Mark Brodwin, Ranga-Ram Chary, Christopher Conselice, Kristen Coppin, Mauro Giavalisco, David Hughes, Rob Ivison, Thushara Perera, Douglas Scott, Kimberly Scott, Grant Wilson Jan 2010

Origins Of The Extragalactic Background At 1mm From A Combined Analysis Of The Aztec And Mambo Data In Goods-N, Kyle Penner, Alexandra Pope, Edward Chapin, Thomas Greve, Frank Bertoldi, Mark Brodwin, Ranga-Ram Chary, Christopher Conselice, Kristen Coppin, Mauro Giavalisco, David Hughes, Rob Ivison, Thushara Perera, Douglas Scott, Kimberly Scott, Grant Wilson

Scholarship

We present a study of the cosmic infrared background, which is a measure of the dust obscured activity in all galaxies in the Universe. We venture to isolate the galaxies responsible for the background at 1mm; with spectroscopic and photometric redshifts we constrain the redshift distribution of these galaxies. We create a deep 1.16mm map (sigma ~ 0.5mJy) by combining the AzTEC 1.1mm and MAMBO 1.2mm datasets in GOODS-N. This combined map contains 41 secure detections, 13 of which are new. By averaging the 1.16mm flux densities of individually undetected galaxies with 24um flux densities > 25uJy, we resolve 31--45 per …


High-Resolution Cavity-Enhanced Spectroscopy Of Molecular Ion Beams, Manori Perera, Andrew Mills, Brian Siller, Michael Porambo, Kyle Crabtree, Carrie Kauffman, Holger Kreckel, Benjamin Mccall Jan 2010

High-Resolution Cavity-Enhanced Spectroscopy Of Molecular Ion Beams, Manori Perera, Andrew Mills, Brian Siller, Michael Porambo, Kyle Crabtree, Carrie Kauffman, Holger Kreckel, Benjamin Mccall

Scholarship

Molecular ions play a pivotal role in the chemistry of the interstellar medium due to their high reactivity even at low temperature. To identify these ions in interstellar space, it is essential to obtain high resolution laboratory spectra of potential interstellar ions for comparison to observational data. At the University of Illinois, we are developing a Sensitive, Cooled, Resolved Ion BEam Spectrometer (SCRIBES) that will allow us to obtain high resolution infrared direct absorption spectra of rotationally cold molecular ions in the absence of neutral molecules. This instrument can overcome many of the problems that arise when using other spectroscopic …


High-Resolution Cavity-Enhanced Spectroscopy Of Molecular Ion Beams, Manori Perera, Andrew Mills, Brian Siller, Michael Porambo, Kyle Crabtree, Carrie Kauffman, Holger Kreckel, Benjamin Mccall Jan 2010

High-Resolution Cavity-Enhanced Spectroscopy Of Molecular Ion Beams, Manori Perera, Andrew Mills, Brian Siller, Michael Porambo, Kyle Crabtree, Carrie Kauffman, Holger Kreckel, Benjamin Mccall

Manori Perera

Molecular ions play a pivotal role in the chemistry of the interstellar medium due to their high reactivity even at low temperature. To identify these ions in interstellar space, it is essential to obtain high resolution laboratory spectra of potential interstellar ions for comparison to observational data. At the University of Illinois, we are developing a Sensitive, Cooled, Resolved Ion BEam Spectrometer (SCRIBES) that will allow us to obtain high resolution infrared direct absorption spectra of rotationally cold molecular ions in the absence of neutral molecules. This instrument can overcome many of the problems that arise when using other spectroscopic …


Linda French, Willis Kern Aug 2006

Linda French, Willis Kern

Interviews for WGLT

Willis Kern interviews Associate Professor of Physics Linda French about her involvement on an advisory panel regarding Pluto's status as a planet. (requires RealPlayer)