Physics Commons^™

Characterizing A Single Photon Detector, Paul N. Rojas

Dissertations, Master's Theses and Master's Reports - Open

I will present my work about constructing and characterizing a single photon detector. Using the 1550nm laser and second harmonic light generation, I am able to count single photons on a Multi‐Pixel Photon Counter (MPPC) silicon APD. My results show that upwards of 22% quantum efficiency is achievable with the MPPC. Future work will include coincidence detection of correlated photon‐pair.

Four-Window Technique For Measuring Optical-Phase-Space-Time-Frequency Tomography, Rachel A. Blaser

Dissertations, Master's Theses and Master's Reports - Open

A new approach, the four-window technique, was developed to measure optical phase-space-time-frequency tomography (OPSTFT). The four-window technique is based on balanced heterodyne detection with two local oscillator (LO) fields. This technique can provide independent control of position, momentum, time and frequency resolution. The OPSTFT is a Wigner distribution function of two independent Fourier transform pairs, phase-space and time-frequency. The OPSTFT can be applied for early disease detection.

Collisional Transfer Of Population And Orientation In Nak, Seth T. Ashman, C. M. Wolfe, J. Bai, B. Beser, E. H. Ahmed, A. M. Lyyra, J. Huennekens

Engineering & Physics Faculty Publications

Collisional satellite lines with |ΔJ| ≤ 58 have been identified in recent polarization spectroscopy V-type optical–optical double resonance (OODR) excitation spectra of the Rb₂ molecule [H. Salami et al., Phys. Rev.A80, 022515 (2009)]. Observation of these satellite lines clearly requires a transfer of population from the rotational level directly excited by the pump laser to a neighboring level in a collision of the molecule with an atomic perturber. However to be observed in polarization spectroscopy, the collision must also partially preserve the angular momentum orientation, which is at least somewhat surprising given the extremely large values of …

Global Analysis Of Data On The Spin-Orbit-Coupled A1Σ+ And B3Πu States Of Cs2, Seth T. Ashman, J. Bai, E H. Ahmed, T. Bergeman

Engineering & Physics Faculty Publications

We present experimentally derived potential curves and spin-orbit interaction functions for the strongly perturbed A1+ u and b3u states of the cesium dimer. The results are based on data from several sources. Laser-induced fluorescence Fourier transform spectroscopy (LIF FTS) was used some time ago in the Laboratoire Aim´e Cotton primarily to study the X1+ g state. More recent work at Tsinghua University provides information from moderate resolution spectroscopy on the lowest levels of the b3± 0u states as well as additional high resolution data. From Innsbruck University, we have precision data obtained with cold Cs2 molecules. Recent data from Temple …

Photonic Non-Destructive Measurement Methods For Investigating The Evolution Of Polar Firn And Ice, Daniel James Breton

Electronic Theses and Dissertations

When snow falls on glaciers or ice sheets, it persists for many tens, hundreds and sometimes thousands of years before becoming ice. The granular material in between fresh snow and glacial ice is known as firn and is generally 50 to 100 m thick over polar ice sheets. The compaction mechanism of firn into ice (called densification) has important glaciological ramifications in determination of ice sheet stability and related sea level rise effects via remote sensing altimetry. Firn densification is also important for correctly interpreting ice core paleoclimate records, especially those analyzing gases trapped in air bubbles within the glacial …

Proton-Proton Correlation Functions As A Probe To Reaction, Micha A. Kilburn '95

Doctoral Dissertations

In an experiment at NSCL, proton-proton (p-p) correlation functions were measured in ⁴⁰Ca+⁴⁰Ca and ⁴⁸Ca+⁴⁸Ca reactions, both at E/A = 80 MeV. The High Resolution Array (HiRA) detected light particles with excellent energy (<200 keV) and angular (~0.2^o) resolution. The MSU 4pi Array covered 77% of the total 4pi solid angle and was used to determine the impact parameter for collisions using transverse energy (E_t) as the relevant observable.

Two-particle correlation functions are employed in this work to measure the space-time …

Equivalent Dynamical Complexity In A Many-Body Quantum And Collective Human System, Neil F. Johnson, Josef Ashkenazi, Zhenyuan Zhao, Luis Quiroga

Physics Articles and Papers

Proponents of Complexity Science believe that the huge variety of emergent phenomena observed throughout nature, are generated by relatively few microscopic mechanisms. Skeptics however point to the lack of concrete examples in which a single mechanistic model manages to capture relevant macroscopic and microscopic properties for two or more distinct systems operating across radically different length and time scales. Here we show how a single complexity model built around cluster coalescence and fragmentation, can cross the fundamental divide between many-body quantum physics and social science. It simultaneously (i) explains a mysterious recent finding of Fratini et al. concerning quantum many-body …

Spitzer Reveals What Is Behind Orion's Bar, Robert H. Rubin, Janet P. Simpson, C. R. O'Dell, Ian A. Mcnabb, Sean W. J. Colgan, Scott Y. Zhuge, Gary J. Ferland, Sergio A. Hidalgo

Physics and Astronomy Faculty Publications

We present Spitzer Space Telescope observations of 11 regions south-east (SE) of the Bright Bar in the Orion Nebula, along a radial from the exciting star θ¹ Ori C, extending from 2.6 to 12.1 arcmin. Our Cycle 5 programme obtained deep spectra with matching Infrared Spectrograph (IRS) short-high (SH) and long-high (LH) aperture grid patterns. Most previous IR missions observed only the inner few arcmin (the ‘Huygens’ Region). The extreme sensitivity of Spitzer in the 10–37 μm spectral range permitted us to measure many lines of interest to much larger distances from θ¹ Ori C. Orion is the …

A Deep Spectroscopic Study Of The Filamentary Nebulosity In Ngc 4696, The Brightest Cluster Galaxy In The Centaurus Cluster, R. E. A. Canning, A. C. Fabian, R. M. Johnstone, J. S. Sanders, C. S. Crawford, Gary J. Ferland, N. A. Hatch

Physics and Astronomy Faculty Publications

We present results of deep integral-field spectroscopy observations using high-resolution optical (4150–7200 Å) VLT VIsible MultiObject Spectrograph spectra of NGC 4696, the dominant galaxy in the Centaurus cluster (Abell 3526). After the Virgo cluster, this is the second nearest (z= 0.0104) example of a cool-core cluster. NGC 4696 is surrounded by a vast, luminous Hα emission-line nebula (L_Hα= 2.2 × 10⁴⁰ erg s⁻¹). We explore the origin and excitation of the emission-line filaments and find their origin consistent with being drawn out, under rising radio bubbles, into the intracluster medium as in …

Detection Of Optical Coronal Emission From 106-K Gas In The Core Of The Centaurus Cluster, R. E. A. Canning, A. C. Fabian, R. M. Johnstone, J. S. Sanders, C. S. Crawford, N. A. Hatch, Gary J. Ferland

Physics and Astronomy Faculty Publications

We report a detection (3.5 × 10³⁷± 5.6 × 10³⁶ erg s⁻¹) of the optical coronal emission line [Fe X] λ6374 and upper limits of four other coronal lines using high-resolution VIMOS spectra centred on NGC 4696, the brightest cluster galaxy in the Centaurus cluster. Emission from these lines is indicative of gas at temperatures between 1 × 10⁶−5 × 10⁶ K, so traces the interstellar gas in NGC 4696. The rate of cooling derived from the upper limits is consistent with the cooling rate from X-ray observations (∼10 M_⊙ yr …

Stability Of A Strongly Anisotropic Thin Epitaxial Film In A Wetting Interaction With Elastic Substrate, Mikhail Khenner, Wondimu T. Tekalign, Margo S. Levine

Mathematics Faculty Publications

The linear dispersion relation for longwave surface perturbations, as derived by Levine et al. Phys. Rev. B 75, 205312 (2007) is extended to include a smooth surface energy anisotropy function with a variable anisotropy strength (from weak to strong, such that sharp corners and slightly curved facets occur on the corresponding Wulff shape). Through detailed parametric studies it is shown that a combination of a wetting interaction and strong anisotropy, and even a wetting interaction alone results in complicated linear stability characteristics of strained and unstrained films.

Stability Of A Strongly Anisotropic Thin Epitaxial Film In A Wetting Interaction With Elastic Substrate, Mikhail Khenner, Wondimu Tekalign, Margo Levine

Mathematics Faculty Publications

The linear dispersion relation for longwave surface perturbations, as derived by Levine et al. Phys. Rev. B 75, 205312 (2007) is extended to include a smooth surface energy anisotropy function with a variable anisotropy strength (from weak to strong, such that sharp corners and slightly curved facets occur on the corresponding Wulff shape). Through detailed parametric studies it is shown that a combination of a wetting interaction and strong anisotropy, and even a wetting interaction alone results in complicated linear stability characteristics of strained and unstrained films.

Modeling Diverse Physics Of Nanoparticle Self-Assembly In Pulsed Laser-Irradiated Metallic Films, Mikhail Khenner

Mathematics Faculty Publications

Presents physics behind dewetting of thin liquid films and mathematical/computational modeling tools (Educational/Research presentation for senior physics majors).

Polarization-Dependent Atomic Dipole Traps Behind A Circular Aperture For Neutral-Atom Quantum Computing, Katharina Gillen-Christandl, Bert D. Copsey

Physics

The neutral-atom quantum computing community has successfully implemented almost all necessary steps for constructing a neutral-atom quantum computer. We present computational results of a study aimed at solving the remaining problem of creating a quantum memory with individually addressable sites for quantum computing. The basis of this quantum memory is the diffraction pattern formed by laser light incident on a circular aperture. Very close to the aperture, the diffraction pattern has localized bright and dark spots that can serve as red-detuned or blue-detuned atomic dipole traps. These traps are suitable for quantum computing even for moderate laser powers. In particular, …

Multi-Wavelength Observations Of The Flaring Gamma-Ray Blazar 3c 66a In 208 October, A. A. Abdo, M. Ackermann, M. Ajello, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, S. Carrigan, J. M. Casandjian, E. Cavazzuti, C. Cecchi, Ö. Çelik, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, L. Costamente, S. Cutini, D. S. Davis, C. D. Dermer, F. De Palma, S. W. Digel, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, C. Favuzzi, S. J. Fegan, P. Fortin, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, J. E. Grove, L. Guillemot, S. Guiriec, D. Hadasch, M. Hayashida, E. Hays, D. Horan, R. E. Hughes, R. Itoh, G. Jóhannesson, A. S. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, S.-H. Lee, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. Makeev, M. N. Mazziotta, J. E. Mcenery, J. Mehault, P. F. Michelson, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Mosalenko, S. Murgia, T. Nakamori, M. Naumann-Godo, I. Nestoras, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, A. Okumura, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Rainò, R. Rando, M. Razzano, A. Reimer, O. Reimer, L. C. Reyes, J. Ripken, S. Ritz, R. W. Romani, M. Roth, H. F.-W. Sadrozinski, D. Sanchez, A. Sander, J. D. Scargle, C. Sgrò, M. S. Shaw, P. D. Smith, G. Spandre, P. Spinelli, M. S. Strickman, D. J. Suson, H. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, T. L. Usher, J. Vandenbroucke, V. Vasileiou, N. Vilchez, V. Vitale, A. P. Waite, P. Wang, B. L. Winer, K. S. Wood, Z. Yang, T. Ylinen, M. Ziegler, V. A. Acciari, E. Aliu, T. Arlen, T. Aune, M. Beilicke, W. Benbow, M. Bottcher, D. Boltuch, S. M. Bradbury, J. H. Buckley, V. Bugaev, K. Byrum, A. Cannon, A. Cesarini, J. L. Christiansen, L. Ciupik, W. Cui, I. De La Calle Perez, R. Dickherber, M. Errando, A. Falcone, J. P. Finley, G. Finnegan, L. Fortson, A. Furniss, N. Galante, D. Gall, G. H. Gillanders, S. Godambe, J. Grube, R. Guenette, G. Gyuk, D. Hanna, J. Holder, C. M. Hui, T. B. Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, D. Kieda, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. Lebohec, G. Maier, S. Mcarthur, A. Mccann, M. Mccutcheon, P. Moriarty, R. Mukherjee, R. A. Ong, A. N. Otte, D. Pandel, J. S. Perkins, A. Pichel, M. Pohl, J. Quinn, K. Ragan, P. T. Reynolds, E. Roache, H. J. Rose, M. Schroedter, G. H. Sembroski, G. D. Senturk, A. W. Smith, D. Steele, S. P. Swordy, G. Tešić, M. Theiling, S. Thibadeau, A. Varlotta, V. V. Vassiliev, S. Vincent, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, T. Weisgarber, D. A. Williams, S. Wissel, M. Wood, M. Villata, C. M. Raiteri, M. A. Gurwell, V. M. Larionov, O. M. Kurtanidze, M. F. Aller, A. Lähteenmäki, W. P. Chen, A. Berduygin, I. Agudo, H. D. Aller, A. A. Arkharov, U. Bach, R. Bachev, P. Beltrame, E. Benitez, C. S. Buemi, J. Dashti, P. Calcidese, D. Capezzali, D. Carosati, D. Da Rio, A. Di Paola, C. Diltz, M. Dolci, D. Dultzin, E. Forne, J. L. Gómez, V. A. Hagen-Thorn, A. Halkola, J. Heidt, D. Hiriart, T. Hovatta, H.-Y. Hsiao, S. G. Jorstad, G. N. Kimeridze, T. S. Konstantinova, E. N. Kopatskaya, E. Koptelova, P. Leto, R. Ligustri, E. Lindfors, J. M. Lopez, A. P. Marscher, M. Mommert, R. Mujica, M. G. Nikolashvili, K. Nilsson, N. Palma, M. Pasanen, M. Roca-Sogorb, J. A. Ros, P. Roustazadeh, A. C. Sadun, J. Saino, L. A. Sigua, A. Sillanää, M. Sorcia, L. O. Takalo, M. Tornikoski, C. Trigilio, R. Turchetti, G. Umana, T. Belloni, C. H. Blake, J. S. Bloom, E. Angelakis, M. Fumagalli, M. Hauser, J. X. Prochaska, D. Riquelme, A. Sievers, D. L. Starr, G. Tagliaferri, H. Ungerechts, S. Wagner, J. A. Zensus

Physics

The BL Lacertae object 3C 66A was detected in a flaring state by the Fermi Large Area Telescope (LAT) and VERITAS in 2008 October. In addition to these gamma-ray observations, F-GAMMA, GASP-WEBT, PAIRITEL, MDM, ATOM, Swift, and Chandra provided radio to X-ray coverage. The available light curves show variability and, in particular, correlated flares are observed in the optical and Fermi-LAT gamma-ray band. The resulting spectral energy distribution can be well fitted using standard leptonic models with and without an external radiation field for inverse Compton scattering. It is found, however, that only the model with an external …

Energy And Environment Chronology, David Hafemeister

Physics

No abstract provided.

Get Away Special: Microgravity Research Team, Getaway Special Team

Education and Outreach

No abstract provided.

Kinematical Conformal Cosmology: Fundamental Parameters From Astrophysical Observations, Gabriele U. Varieschi

Physics Faculty Works

No abstract provided.

Long-Range And Short-Range Dihadron Angular Correlations In Central Pbpb Collisions At Psnn = 2:76 Tev, S. Chatrchyan, Marc M. Baarmand, B. Dorney, Samir Guragain, Marcus Hohlmann, Himali Kalakhety, Robert Ralich, Igor Vodopiyanov, The Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

First measurements of dihadron correlations for charged particles are presented for central PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV over a broad range in relative pseudorapidity (∆η) and the full range of relative azimuthal angle (∆η). The data were collected with the CMS detector, at the LHC. A broadening of the away-side (∆ϕ ≈ π) azimuthal correlation is observed at all ∆η, as compared to the measurements in pp collisions. Furthermore, long-range dihadron correlations in ∆η are observed for particles with similar ϕ values. This phenomenon, also known as the “ridge”, persists up to at least |∆η| …

Search For Light Resonances Decaying Into Pairs Of Muons As A Signal Of New Physics, S. Chatrchyan, Marc M. Baarmand, B. Dorney, Samir Guragain, Marcus Hohlmann, Himali Kalakhety, Robert M. Ralich, Igor Vodopiyanov, The Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A search for groups of collimated muons is performed using a data sample collected by the CMS experiment at the LHC, at a centre-of-mass energy of 7 TeV, and corresponding to an integrated luminosity of 35 pb−1 . The analysis searches for production of new low-mass states decaying into pairs of muons and is designed to achieve high sensitivity to a broad range of models predicting leptonic jet signatures. With no excess observed over the background expectation, upper limits on the production cross section times branching fraction times acceptance are set, ranging from 0.1 to 0.5 pb at the 95% …