Astrophysics and Astronomy Commons^™

Teaching Big History, Richard B. Simon, Mojgan Behmand, Thomas Burke, Esther Quaedackers, Seohyung Kim, Kiowa Bower, Neal Wolfe, James B. Cunningham, Cynthia Taylor, Martin Anderson, J. Daniel May, Philip Novak, Debbie Daunt, Jaime Castner, Ethan Annis, Amy E. Gilbert, Anne Reid, Suzanne Roybal, Alan Schut, Cynthia Brown, Harlan Stelmach

Harlan Stelmach

Photometric Study Of The Short-Period Eclipsing Binary V441 Lac, Daimei Wang, Liyun Zhang, Xianming Han, Franz Agerer, Qingfeng Pi, Shuai Wang

Xianming Han

We present the first multi-color VRI CCD light curves of a short-period eclipsing binary star v441 Lac in this paper. We obtained our light curves on Oct. 4 and 8, 2013 at Xinglong station of National Astronomical Observatories, China. We updated the ephemeris of V441 Lac based on three new minima derived by our new observational data together with previously available light curve minima. By fitting the O−C (observed minus calculated) values of the minima, we found that the orbital period of V441 Lac exhibits an increasing trend of Ṗ=5.67(0.35)×10^-7 days/year, which might be explained by mass transfer from the …

The First Multi-Color Photometric Study Of The Short-Period Contact Eclipsing Binary Gk Aqr, Liyun Zhang, Qingfeng Pi, Xianming Han, Tongan Li, Xiliang Zhang, Hongyan Sang, Daimei Wang, Shuai Wang

Xianming Han

We made the first VRI CCD light curves of the short-period contact eclipsing binary GK Aqr, which was observed on October 5 and 8, 2013 at Xinglong station of National Astronomical Observatories, China. The ephemeris of GK Aqr was calculated based on our two newly obtained minima and the minima that other observers obtained previously. We discovered that the orbital period of GK Aqr exhibits an increasing trend of Ṗ=2.8(0.1)×10^-7 days/year by means of fitting the O-C values of the minima. This phenomenon might be explained by mass transfer from the primary (less massive) component to the secondary (more massive) …

Lightcurve Analysis Of Four Asteroids, Bin Li, Haibin Zhao, Xianming Han, Lina Annable, Eli Finkel, Orry Heffner, Adam Kidd, Bradley Magnetta, Tiffany Ramires, Frederick Rastede, Sean Sproston

Xianming Han

From June 2011 through May 2012 May, photometric data for four asteroids were obtained using the Southeastern Association for Research in Astronomy (SARA) telescope located at the Kitt Peak National Observatory. The following synodic periods were found: 4808 Ballaero, P = 8.8976 ± 0.0007 h; 7750 McEwen, P = 27.82 ± 0.01 h; 11941 Archinal, P = 2.717 ±0.006 h; and (47035) 1998WS, P = 7.996 ± 0.001 h.

Dr. Linda French: Don’T Limit Yourself (Interview With Kelsi Singer), Linda French

Linda French

Dr. Linda French is Professor of Physics and past Chair of the Physics Department at Illinois Wesleyan University, where she has been a professor since 2002. She received her A.B. in astronomy from Indiana University and a Ph. D. in planetary astronomy from Cornell University. Her scientific research, funded by the National Science Foundation, concerns the study of the shapes and surfaces of asteroids and comets. She is a frequent guest observer at Lowell Observatory in Arizona and at Cerro Tololo Interamerican Observatory in Chile, and is often accompanied by students on these research trips.

The Lyman Alpha Reference Sample: Iv. Morphology At Low And High Redshift, L. Guaita, J. Melinder, M. Hayes, G. Ostlin, J. Gonzalez, A. Adamo, J. Mas-Hesse, A. Sandberg, H. Oti-Floranes, D. Schaerer, A. Verhamme, E. Freeland, I. Orlitova, P. Laursen, John Cannon, F. Duval, T. Rivera-Thorsen, E. Herenz, D. Kunth, H. Atek, J. Puschnig, P. Gruyters, S. Pardy

John Cannon

No abstract provided.

Oxygen Abundance Measurements Of Shield Galaxies, N. Haurberg, J. Salzer, John Cannon, M. Marshall

John Cannon

No abstract provided.

Agc198606: A Gas-Bearing Dark Matter Minihalo?, E. Adams, Y. Faerman, W. Janesh, S. Janowiecki, T. Oosterloo, K. Rhode, R. Giovanelli, M. Haynes, J. Salzer, A. Sternberg, John Cannon, R. Munoz

John Cannon

No abstract provided.

The Alfalfa "Almost Darks" Campaign: Pilot Vla Hi Observations Of Five High Mass-To-Light Ratio Systems, John Cannon, C. Martinkus, L. Leisman, M. Haynes, E. Adams, R. Giovanelli, G. Hallenbeck, S. Janowiecki, M. Jones, G. Josza, R. Koopmann, N. Nichols, E. Papastergis, K. Rhode, J. Salzer, P. Trosicht

John Cannon

No abstract provided.

(Almost) Dark Hi Sources In The Alfalfa Survey: The Intriguing Case Of Hi1232+20, Steven Janowiecki, Lukas Leisman, Gyula Jozsa, John Salzer, Martha Haynes, Riccardo Giovanelli, Katherine Rhode, John Cannon, Elizabeth Adams, William Janesh

John Cannon

No abstract provided.

The Lyman Alpha Reference Sample: V. Empirical Inferences On The Lyman Alpha Output From High-Resolution Ultraviolet Spectroscopy, T. Rivera-Thorsen, M. Hayes, G. Ostlin, F. Duval, I. Orlitova, A. Verhamme, J. Mas-Hesse, D. Schaerer, John Cannon, H. Oti-Floranes, A. Sandberg, L. Guaita, A. Adamo, H. Atek, E. Herenz, D. Kunth, P. Laursen, J. Melinder

John Cannon

No abstract provided.

Characterizing The Star Formation Of The Low-Mass Shield Galaxies From Hubble Space Telescope Imaging, K. Mcquinn, John Cannon, A. Dolphin, E. Skillman, M. Haynes, J. Simones, J. Salzer, E. Adams, E. Elson, R. Giovanelli, J. Ott

John Cannon

No abstract provided.

Carrier Heating And Negative Photoconductivity In Graphene, James Heyman, J. D. Stein, Z. S. Kaminski, A. R. Banman, A. M. Massari, J. T. Robinson

James Heyman

No abstract provided.

Teaching Threshold 6: The Rise Of Homo Sapiens, Richard Simon, Mojgan Behmand, Thomas Burke, Esther Quaedackers, Seohyung Kim, Kiowa Bower, Neal Wolfe, James Cunningham, Cynthia Taylor, Martin Anderson, J. May, Philip Novak, Debbie Daunt, Jaime Castner, Ethan Annis, Amy Gilbert, Anne Reid, Suzanne Roybal, Alan Schut, Cynthia Brown, Harlan Stelmach

Cynthia Taylor

Teaching Big History, Richard B. Simon, Mojgan Behmand, Thomas Burke, Esther Quaedackers, Seohyung Kim, Kiowa Bower, Neal Wolfe, James B. Cunningham, Cynthia Taylor, Martin Anderson, J. Daniel May, Philip Novak, Debbie Daunt, Jaime Castner, Ethan Annis, Amy E. Gilbert, Anne Reid, Suzanne Roybal, Alan Schut, Cynthia Brown, Harlan Stelmach

Mojgan Behmand

Teaching Big History Or Teaching About Big History? Big History And Religion, Harlan Stelmach

Harlan Stelmach

The Lyman Alpha Reference Sample: Iii. Properties Of The Neutral Ism From Gbt And Vla Observations, Stephen Pardy, John Cannon, Göran Östlin, Matthew Hayes, Thøger Rivera-Thorsen, Andreas Sandberg, Angela Adamo, Emily Freeland, E. Herenz, Lucia Guaita, Daniel Kunth, Peter Laursen, J. Mas-Hesse, Jens Melinder, Ivana Orlitova, Hecto Otí-Floranes, Johannes Puschnig, Daniel Schaerer, Anne Verhamme

John Cannon

No abstract provided.

Comparative Analysis Of A Transition Region Bright Point With A Blinker And Coronal Bright Point Using Multiple Eis Emission Lines, N Orange, H Oluseyi, D Chesny, M Patel, K Hesterly, L Preuss, C Neira, Niescja Turner

Niescja E. Turner

Since their discovery 20 year ago, transition region bright points have never been observed spectroscopically. Bright point properties have not been compared with similar transition region and coronal structures. In this work we have investigated three transient quiet Sun brightenings including a transition region bright point (TR BP), a coronal bright point (CBP) and a blinker. We use time-series observations of the extreme-ultraviolet emission lines of a wide range of temperature T(logT=5.3 – 6.4) from the EUV Imaging Spectrometer (EIS) onboard the Hinode satellite. We present the EIS temperature maps and Doppler maps, which are compared with magnetograms from theMichelson …

Growth Of Carbon Grains In Supernova Ejecta, Ethan Deneault, Donald Clayton, Bradley Meyer

Donald D Clayton

We present a chemical reaction network that describes the condensation chemistry of carbon dust grains in an expanding supernova shell. We assume that the region of interest consists solely of gaseous free carbon and oxygen atoms and that the buildup of CO is counteracted by the radioactive decay of 56Co, which breaks up the CO mol-ecule and allows C to condense into solids. Our chemical model takes C to first form linear chains, which, at some critical length, transition into ringed isomers. These isomers are more resistant to oxidation than linear chains. These ringed isomers form the nuclei for the …

Are Ti44-Producing Supernovae Exceptional?, L.-S. The, Donald Clayton, R Diehl, Dieter Hartmann, A Iyudin, M Leising, B Meyer, Y Motizuki, V Schönfelder

Donald D Clayton

According to standard models supernovae produce radioactive 44Ti, which should be visible in gamma-rays following decay to 44Ca for a few centuries. 44Ti production is believed to be the source of cosmic 44Ca, whose abundance is well established. Yet, gamma-ray telescopes have not seen the expected young remnants of core collapse events. The 44Ti mean life of 89 y and the Galactic supernova rate of 3/100 y imply several detectable 44Ti gamma-ray sources, but only one is clearly seen, the 340-year-old Cas A SNR. Furthermore, supernovae which produce much 44Ti are expected to occur primarily in the inner part of …

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

Sean D Brittain

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 columndensity ratio and disk inclination similar to that found by Rettig et al.

Gas In Protoplanetary Systems (Gasps). I. First Results, G Mathews, W.R.F. Dent, J Williams, C Howard, G Meeus, B Riaz, A Roberge, G Sandell, B Vandenbussche, G Duchene, I Kamp, F Menard, B Montesinos, C Pinte, W. Thi, P Woitke, J Alacid, S Andrews, D Ardila, G Aresu, J Augereau, D Barrado, Sean Brittain

Sean D Brittain

Context. Circumstellar discs are ubiquitous around young stars, but rapidly dissipate their gas and dust on timescales of a few Myr. The Herschel Space Observatory allows for the study of the warm disc atmosphere, using far-infrared spectroscopy to measure gas content and excitation conditions, and far-IR photometry to constrain the dust distribution. Aims. We aim to detect and characterize the gas content of circumstellar discs in four targets as part of the Herschel science demonstration phase. Methods. We carried out sensitive medium resolution spectroscopy and high sensitivity photometry at λ ∼60–190 μm using the Photodetector Array Camera and Spectrometer instrument …

The Unusual Protoplanetary Disk Around The T Tauri Star Et Chamaeleontis, P Woitke, B Riaz, G Duchene, I Pascucci, A Ran Lyo, W.R.F. Dent, N Phillips, W Thi, F Menard, G Herczeg, E Bergin, A Brown, A Mora, I Kamp, G Aresu, Sean Brittain, I De Gregorio-Monsalvo, G Sandell

Sean D Brittain

We present new continuum and line observations, along with modelling, of the faint (6−8) Myr old T Tauri star ETCha belonging to the η Chamaeleontis cluster. We have acquired Herschel/PACS photometric fluxes at 70 μm and 160 μm, as well as a detection of the [OI] 63 μm fine-structure line in emission, and derived upper limits for some other far-IR OI, CII, CO and o-H2O lines. These observations were carried out in the frame of the open time key programme GASPS, where ETCha was selected as one of the science demonstration phase targets. The Herschel data is complemented by new …

Hd 100453: A Link Between Gas-Rich Protoplanetary Disks And Gas-Poor Debris Disks, K Collins, C Grady, K Hamaguchi, J Wisniewski, Sean Brittain, M Sitko, W Carpenter, J Williams, G Mathews, G Williger, R Van Boekel, A Carmona, Th. Henning, M Van Den Ancker, G Meeus, X Chen, R Petre, B Woodgate

Sean D Brittain

HD 100453 has an IR spectral energy distribution (SED) which can be fit with a power law plus a blackbody. Previous analysis of the SED suggests that the system is a young Herbig Ae star with a gas-rich, flared disk. We reexamine the evolutionary state of the HD 100453 system by refining its age (based on a candidate low-mass companion) and by examining limits on the disk extent, mass accretion rate, and gas content of the disk environment. We confirm that HD 100453B is a common proper motion companion to HD 100453A, with a spectral type of M4.0V-M4.5V, and derive …

Astronomy Matters For Chemistry Teachers, Terry Smith, Jay Huebner, Robert Vergenz

Jay S Huebner

The purpose of this paper is to encourage more chemistry teachers to become familiar with some of the basic ideas described in typical introductory astronomy courses (1 - 9), including those about the origin of elements and forms of matter. These ideas would enrich chemistry courses and help resolve some basic misconceptions that are expressed in many introductory texts (10 - 16) and journal articles for chemistry teachers (17, 18). These misconceptions are typified by statements such as "we can classify all substances as either elements or compounds," and "nature has provided 92 elements out of which all matter is …

Finite Difference Schemes For Second Order Systems Describing Black Holes, Mohammad Motamed, Maria Babiuc-Hamilton, B. Szilágyi, H-O. Kreiss, J. Winicour

Maria Babiuc-Hamilton

In the harmonic description of general relativity, the principal part of Einstein’s equations reduces to 10 curved space wave equations for the components of the space-time metric. We present theorems regarding the stability of several evolution-boundary algorithms for such equations when treated in second order differential form. The theorems apply to a model black hole space-time consisting of a spacelike inner boundary excising the singularity, a timelike outer boundary and a horizon in between. These algorithms are implemented as stable, convergent numerical codes and their performance is compared in a 2-dimensional excision problem.

Dark Matter As An Integral Part Of An Alternative Gravity Model, Hontas Farmer

Hontas F Farmer

The purpose of this paper is to reconcile observations of dark matter effects on the galactic and cosmological scales with the null results of astroparticle physics observations such as CDMS and ANTARES. This paper will also provide a candidate unified and simpler mathematical formulation for the Lambda CDM model. Unification is achieved by a combination of the f(R) approach, with the standard LCDM approach and inflationary models. It is postulated that dark matter-energy fields depend on the Ricci curvature R. Standard methods of classical and quantum field theory on curved space time are applied. When this model is treated as …

Disk-Outflow Models As Applied To High Mass Star Forming Regions Through Methanol And Water Maser Observations, Hontas Farmer

Hontas F Farmer

As the recent publication by Breen et al (2013) found Class II methanol masers are exclusively associated with high mass star forming regions. Based on the positions of the Class I and II methanol and H2O masers, UC H~II regions and 4.5~μm infrared sources, and the center velocities (vLSR) of the Class I methanol and H2O masers, compared to the vLSR of the Class II methanol masers, we propose three disk-outflow models that may be traced by methanol masers. In all three models, we have located the Class II methanol maser near the protostar, and the Class I methanol maser …

The Molecular Gas Reservoir Of 6 Low-Metallicity Galaxies From The Herschel Dwarf Galaxy Survey: A Ground-Based Follow-Up Survey Of Co(1-0), Co(2-1), And Co(3-2), D. Cormier, S. Madden, V. Lebouteiller, S. Hony, S. Aalto, F. Costagliola, A. Huges, N. Abel, E. Bayet, John Cannon, R. Cumming, M. Galametz, F. Galliano, A. Remy-Ruyer, S. Viti, R. Wu

John Cannon

No abstract provided.

An Extremely Optically Dim Tidal Feature In The Gas-Rich Interacting Galaxy Group Ngc 871/Ngc 876/Ngc 877, K. Lee-Waddell, K. Spekkens, J.-C. Cuillandre, John Cannon, M. Haynes, J. Sick, P. Chandra, N. Patra, S. Stierwalt, R. Giovanelli

John Cannon

No abstract provided.