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Full-Text Articles in Physical Sciences and Mathematics

Proposed Coherent Trapping Of A Population Of Electrons In A C60 Molecule Induced By Laser Excitation, Thomas George, G.P. Zhang Nov 2012

Proposed Coherent Trapping Of A Population Of Electrons In A C60 Molecule Induced By Laser Excitation, Thomas George, G.P. Zhang

Chemistry & Biochemistry Faculty Works

This Letter demonstrates the possibility of generating coherent population trapping in C60. Similar to a three-level Λ system, C60 has a forbidden transition between the highest occupied molecular orbital (HOMO) (|a⟩) and the lowest unoccupied molecular orbital (LUMO) (|c⟩), but a dipole-allowed transition between HOMO and LUMO+1 (|b⟩) and between |b⟩ and |c⟩. We employ two cw laser fields, one coupling and one probe. The strong coupling field is switched on first to resonantly excite the transition between |b⟩ and |c⟩. After a delay, the probe is switched on; the coherent interaction between the coupling and probe fields traps the …


[Accepted Article Manuscript Version (Postprint)] Track Me To Track Us: Leveraging Short Range Wireless Technologies For Enabling Energy Efficient Wi-Fi-Based Localization, Mohamed Abdellatif, Abderrahmen Mtibaa, Khaled Harras Oct 2012

[Accepted Article Manuscript Version (Postprint)] Track Me To Track Us: Leveraging Short Range Wireless Technologies For Enabling Energy Efficient Wi-Fi-Based Localization, Mohamed Abdellatif, Abderrahmen Mtibaa, Khaled Harras

Computer Science Faculty Works

Given the success of outdoor tracking via GPS and the rise of real-time context-aware services, users will soon rely on applications that require higher granularity indoor localization. This need is further manifested in countries like Qatar, where various social and business activities occur indoors. Wi-Fi-based indoor localization is one of the most researched techniques due to its ubiquitous deployment and acceptable accuracy for a wide range of applications. However, we do not witness such techniques widely deployed mainly due to their high demand on energy, which is a precious commodity in mobile devices. We propose an energy-efficient indoor localization system …


A Proper Motion Study Of The Haro 6-10 Outflow: Evidence For A Subarcsecond Binary, Bruce Wilking, Kevin Marvel, Mark Claussen, Bradley Gerling, Alwyn Wootten, Erika Gibb Jul 2012

A Proper Motion Study Of The Haro 6-10 Outflow: Evidence For A Subarcsecond Binary, Bruce Wilking, Kevin Marvel, Mark Claussen, Bradley Gerling, Alwyn Wootten, Erika Gibb

Physics Faculty Works

We present single-dish and very long baseline interferometry observations of an outburst of water maser emission from the young binary system Haro 6-10. Haro 6-10 lies in the Taurus molecular cloud and contains a visible T Tauri star with an infrared companion 1farcs3 north. Using the Very Long Baseline Array, we obtained five observations spanning three months and derived absolute positions for 20 distinct maser spots. Three of the masers can be traced over three or more epochs, enabling us to extract absolute proper motions and tangential velocities. We deduce that the masers represent one side of a bipolar outflow …


The Gas/Dust Ratio Of Circumstellar Disks: Testing Models Of Planetesimal Formation, David Horne, Erika Gibb, Terrence Rettig, Sean Brittain, David Tilley, Dinshaw Balsara Jul 2012

The Gas/Dust Ratio Of Circumstellar Disks: Testing Models Of Planetesimal Formation, David Horne, Erika Gibb, Terrence Rettig, Sean Brittain, David Tilley, Dinshaw Balsara

Physics Faculty Works

We present high-resolution, near-infrared NIRSPEC observations of CO absorption toward six class II T Tauri stars: AA Tau, DG Tau, IQ Tau, RY Tau, CW Tau, and Haro 6-5b. 12CO overtone absorption lines originating from the circumstellar disk of each object were used to calculate line-of-sight gas column densities toward each source. We measured the gas/dust ratio as a function of disk inclination, utilizing measured visual extinctions and inclinations for each star. The majority of our sources show further evidence for a correlation between the gas/dust column density ratio and disk inclination similar to that found by Rettig et al.


Chemical Composition Of Comet C/2007 N3 (Lulin): Another ''Atypical'' Comet, Erika Gibb, Boncho Bonev, Geronimo Villanueva, Michael Disanti, Michael Mumma, Emily Sudholt, Yana Radeva May 2012

Chemical Composition Of Comet C/2007 N3 (Lulin): Another ''Atypical'' Comet, Erika Gibb, Boncho Bonev, Geronimo Villanueva, Michael Disanti, Michael Mumma, Emily Sudholt, Yana Radeva

Physics Faculty Works

We measured the volatile chemical composition of comet C/2007 N3 (Lulin) on three dates from 2009 January 30 to February 1 using NIRSPEC, the high-resolution (λ/Δλ ≈ 25,000), long-slit echelle spectrograph at Keck 2. We sampled nine primary (parent) volatile species (H2O, C2H6, CH3OH, H2CO, CH4, HCN, C2H2, NH3, CO) and two product species (OH* and NH2). We also report upper limits for HDO and CH3D. C/2007 N3 (Lulin) displayed an unusual composition when compared to other comets. Based on comets measured to date, CH4 and C2H6 exhibited "normal" abundances relative to water, CO and HCN were only moderately depleted, …


Synthesis Of Some Aminopicolinic Acids, Alicia Beatty, Ramadan Bawa Apr 2012

Synthesis Of Some Aminopicolinic Acids, Alicia Beatty, Ramadan Bawa

Chemistry & Biochemistry Faculty Works

Some aminopicolinic acid derivatives have been synthesized and fully characterized. These pyridine derivatives were 4-aminopicolinic acid, 4-(4-aminophenylethynyl) picolinic acid and 4-(3-aminophenylethynyl) picolinic acid. In addition to these compounds, other substituted picolinic acids were made throughout the synthetic paths.


2-Allylphenyl Glycosides As Complementary Building Blocks For Oligosaccharide And Glycoconjugate Synthesis, Hemali Premathilake, Alexei Demchenko Apr 2012

2-Allylphenyl Glycosides As Complementary Building Blocks For Oligosaccharide And Glycoconjugate Synthesis, Hemali Premathilake, Alexei Demchenko

Chemistry & Biochemistry Faculty Works

The O-allylphenyl (AP) anomeric moiety was investigated as a new leaving group that can be activated for chemical glycosylation under a variety of conditions, through both direct and remote pathways. Differentiation between the two activation pathways was achieved in a mechanistic study. The orthogonal-type activation of the AP moiety along with common thioglycosides allows for the execution of efficient oligosaccharide assembly.