An Unusually Fast-Evolving Supernova (2009)
Poznanski, Dovi, Chornock, Ryan, Nugent, Peter E., Bloom, Joshua S., Ganeshalingam, Mohan, Leonard, Douglas C., ...
Analyses of supernovae (SNe) have revealed two main types of progenitors: exploding white dwarfs and collapsing massive stars. We present SN2002bj, which stands out as different from any SN reported...
First-principles LDA+U and GGA+U study of neptunium dioxide (2009)
Wang, Baotian, Shi, Hongliang, Li, Weidong, Zhang, Ping
We have performed a systematic first-principles investigation to calculate the electronic structures, mechanical properties, and phonon dispersion curves of NpO$_{2}$. The local density...
Folatelli, Gaston, Phillips, M. M., Burns, Christopher R., Contreras, Carlos, Hamuy, Mario, Freedman, W. L., ...
We present the analysis of the first set of low-redshift Type Ia supernovae (SNe Ia) by the Carnegie Supernova Project. Well-sampled, high-precision optical (ugriBV) and near-infrared (NIR; YJHKs)...
Contreras, Carlos, Hamuy, Mario, Phillips, M. M., Folatelli, Gaston, Suntzeff, Nicholas B., Persson, S. E., ...
The Carnegie Supernova Project (CSP) is a five-year survey being carried out at the Las Campanas Observatory to obtain high-quality light curves of ~100 low-redshift Type Ia supernovae in a...
Walsh, Jonelle L., Minezaki, Takeo, Bentz, Misty C., Barth, Aaron J., Baliber, Nairn, Li, Weidong, ...
The Lick AGN Monitoring Project targeted 13 nearby Seyfert 1 galaxies with the intent of measuring the masses of their central black holes using reverberation mapping. The sample includes 12 galaxies...
Smith, Nathan, Miller, Adam A., Li, Weidong, Filippenko, Alexei V., Silverman, Jeffrey M., Howard, Andrew W., ...
We present progenitor star detections, light curves, and spectra of SN 2009ip and the 2009 optical transient in UGC 2773 (U2773-OT), which were not genuine supernovae (SNe). In particular, precursor...
Variable Sodium Absorption in a Low-extinction Type Ia Supernova (2009)
Simon, Joshua D., Gal-Yam, Avishay, Gnat, Orly, Quimby, Robert M., Ganeshalingam, Mohan, Silverman, Jeffrey M., ...
Recent observations have revealed that some Type Ia supernovae exhibit narrow, time-variable Na I D absorption features. The origin of the absorbing material is controversial, but it may suggest the...
Wang, Baotian, Shao, Jianli, Zhang, Guangcai, Li, Weidong, Zhang, Ping
Molecular dynamics simulations are performed to investigate the structural phase transition in body-centered cubic (bcc) single crystal iron under high strain rate loading. We study the nucleation...
First-principles study of ground state properties and high pressure behavior of ThO2 (2009)
Wang, Baotian, Shi, Hongliang, Li, Weidong, Zhang, Ping
The mechanical properties, electronic structure and phonon dispersion of ground state ThO$_{2}$ as well as the structure behavior up to 240 GPa are studied by using first-principles...
Bentz, Misty C., Walsh, Jonelle L., Barth, Aaron J., Baliber, Nairn, Bennert, Nicola, Canalizo, Gabriela, ...
We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05)...
Variable Sodium Absorption in a Low-Extinction Type Ia Supernova (2009)
Simon, Joshua D., Gal-Yam, Avishay, Gnat, Orly, Quimby, Robert M., Ganeshalingam, Mohan, Silverman, Jeffrey M., ...
Recent observations have revealed that some Type Ia supernovae exhibit narrow, time-variable Na I D absorption features. The origin of the absorbing material is controversial, but it may suggest the...
Mechanical and chemical bonding properties of ground state BeH$_2$ (2009)
Wang, Bao-Tian, Zhang, Ping, Shi, Hongliang, Sun, Bo, Li, Weidong
The crystal structure, mechanical properties and electronic structure of ground state BeH$_{2}$ are calculated employing the first-principles methods based on the density functional theory. Our...
Riess, Adam G., Macri, Lucas, Casertano, Stefano, Sosey, Megan, Lampeitl, Hubert, Ferguson, Henry C., ...
We report observations of 240 Cepheid variables obtained with the Near Infrared Camera (NICMOS) through the F160W filter on the Hubble Space Telescope (HST). The Cepheids are distributed across six...
Cepheid Calibrations of Modern Type Ia Supernovae:Implications for the Hubble Constant (2009)
Riess, Adam G., Macri, Lucas, Li, Weidong, Lampeitl, Hubert, Casertano, Stefano, Ferguson, Henry C., ...
This is the first of two papers reporting measurements from a program to determine the Hubble constant to 5% precision from a refurbished distance ladder. We present new observations of 110 Cepheid...
Xue, Rui, Liang, Z. X., Li, Weidong
A set of exact closed-form Bloch-state solutions to the stationary Gross-Pitaevskii equation are obtained for a Bose-Einstein condensate in a one-dimensional periodic array of quantum wells, i.e. a...
Type II Supernovae as Probes of Cosmology (2009)
Poznanski, Dovi, Baron, Eddie, Blondin, Stephane, Bloom, Joshua S., D'Andrea, Christopher B., Della Valle, Massimo, ...
- Constraining the cosmological parameters and understanding Dark Energy have tremendous implications for the nature of the Universe and its physical laws. - The pervasive limit of systematic...
SN 2008ha: An Extremely Low Luminosity and Extremely Low Energy Supernova (2009)
Foley, Ryan J., Chornock, Ryan, Filippenko, Alexei V., Ganeshalingam, Mohan, Kirshner, Robert P., Li, Weidong, ...
We present ultraviolet, optical, and near-infrared photometry as well as optical spectra of the peculiar supernova (SN) 2008ha. SN 2008ha had a very low peak luminosity, reaching only M_V = -14.2...
Variable sodium absorption in a low-extinction type Ia supernova (2009)
Simon, Joshua D., Gal-Yam, Avishay, Gnat, Orly, Quimby, Robert M., Ganeshalingam, Mohan, Silverman, Jeffrey M., ...
Soil properties (or variables) are usually classifi ed into multiple classes (or intervals) and delineated as area-class (i.e., polygon) maps. Area-class soil maps are widely used in soil science and...
1 AN FFT PROCESSOR BASED ON 16-POINT MODULE (2008)
Weidong Li, Mark Vesterbacka, Lars Wanhammar
The number of multiplications has been a key merit for FFT algorithms. It has important impact on the total power consumption. In this paper, we present a 16-point FFT module, which reduces the...
GML-Based Interoperable Geographical Databases (2008)
Chuanrong Zhang, Zhong-ren Peng, Weidong Li, Micheal J. Day
Many geographical databases have been developed by different programs and applications, but data acquisition and data sharing are still a big problem because no interoperability exists among these...
Understanding Multiplier Design using “Overturned-Stairs ” Adder Trees (2008)
Magnus Karlsson, Oscar Gustafsson, J Jacob Wikner, Thomas Johansson, Weidong Li, Magnus Hörlin, ...
Abstract – Different tree structures are used in high-speed multipliers. One type of trees, the overturned-stairs adder trees of the first order, OS 1 trees, is described in this report. They show...
1. Abstract The nonlinear Markov Chain Geostatistics (2008)
With the proposition of a Markov chain random field (MCRF) theory and its accompanying spatial measure – the transiogram, Markov chain has been extended into a nonlinear Markov chain-based...
Smith, Nathan, Chornock, Ryan, Li, Weidong, Ganeshalingam, Mohan, Silverman, Jeffrey M., Foley, Ryan J., ...
SN2006tf is the third most luminous SN discovered so far, after SN2005ap and SN2006gy. SN2006tf is valuable because it provides a link between two regimes: (1) luminous type IIn supernovae powered by...
Late-time observations of SN2006gy: Still Going Strong (2008)
Smith, Nathan, Foley, Ryan J., Bloom, Joshua S., Li, Weidong, Filippenko, Alexei V., Gavazzi, Raphael, ...
Owing to its extremely high luminosity and long duration, SN2006gy radiated more energy in visual light than any other known SN. Two hypotheses to explain its high luminosity -- that it was powered...
Chien Y. Peng, Jennifer Y. King, Richard R. Treffers, Weidong Li, Michael W. Richmond
To be submitted to the Publications of the Astronomical Society of the Pacific Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive of the Space...
Saurabh Jha, Peter M. Garnavich, Robert P. Kirshner, Peter Challis, Alicia M. Soderberg, Lucas M. Macri, ...
We present optical and near-infrared photometry and spectroscopy of the Type Ia SN 1998bu in the Leo I Group galaxy M96 (NGC 3368). The data set consists of 356 photometric measurements and 29...
On the Progenitor of SN 2005gl and the Nature of Type IIn Supernovae (2007)
Gal-Yam, Avishay, Leonard, D. C., Fox, D. B., Cenko, S. B., Soderberg, A. M., ...
We present a study of the Type IIn supernova (SN) 2005gl, in the relatively nearby (d ≈ 66 Mpc) galaxy NGC 266. Photometry and spectroscopy of the SN indicate that it is a typical member of its...
SN 2006jc: A Wolf-Rayet Star Exploding in a Dense He-Rich Circumstellar Medium (2006)
Foley, Ryan J., Smith, Nathan, Ganeshalingam, Mohan, Li, Weidong, Chornock, Ryan, Filippenko, Alexei V.
We present optical photometry and spectra of the peculiar Type Ib supernova (SN) 2006jc. Strong and relatively narrow He I emission lines indicate the progenitor star exploded inside a dense...
In the present paper we investigate the influence of measurements on the quantum dynamics of degenerate Bose atoms gases in a symmetric double-well. We show that continuous measurements enhance...
The stationary solutions of G-P equations in double square well (2006)
We present analytical stationary solutions for the Gross-Pitaevskii equation (GPE) of a Bose-Einstein condensate (BECs) trapped in a double-well potential. These solutions are compared with those...
Sn 2005bf: A possible transition event between type Ib/c supernovae and gamma-ray bursts (2006)
Folatelli, Gastón, Contreras, Carlos, Phillips, M. M., Woosley, S. E., Blinnikov, Sergei, Morrell, Nidia, ...
We present u'g'r'i'BV photometry and optical spectroscopy of the Type Ib/Ic SN 2005bf covering the first similar to 100 days following discovery. The u'g'BV light curves displayed an unprecedented...
Spectropolarimetry of the Peculiar Type Ia SN 2005hk (2006)
Chornock, Ryan, Filippenko, Alexei V., Branch, David, Foley, Ryan J., Jha, Saurabh, Li, Weidong
We present Keck spectropolarimetry of the unusual type Ia supernova (SN Ia) 2005hk several days before maximum light. An analysis of the high signal-to-noise-ratio total-flux spectrum shows the...
The Carnegie Supernova Project: The low-redshift survey (2006)
Hamuy, Mario, Folatelli, Gastón, Morrell, Nidia I., Phillips, Mark M., Suntzeff, Nicholas B., Persson, S. E., ...
Supernovae are essential to understanding the chemical evolution of the universe. Type Ia supernovae also provide the most powerful observational tool currently available for studying the expansion...
Using Line Profiles to Test the Fraternity of Type Ia Supernovae at High and Low Redshifts (2006)
Blondin, Stéphane, Dessart, Luc, Leibundgut, Bruno, Branch, David, Höflich, Peter, Tonry, John L., ...
Using archival data of low-redshift (z < 0.01; Center for Astrophysics and SUSPECT databases) Type Ia supernovae (SNe Ia) and recent observations of high-redshift (0.16 < z < 0.64) SNe Ia, we study...
Using Line Profiles to Test the Fraternity of Type Ia Supernovae at High and Low Redshifts (2006)
Blondin, Stéphane, Dessart, Luc, Leibundgut, Bruno, Branch, David, Höflich, Peter, Tonry, John L., ...
Using archival data of low-redshift (z < 0.01; Center for Astrophysics and SUSPECT databases) Type Ia supernovae (SNe Ia) and recent observations of high-redshift (0.16 < z < 0.64) SNe Ia, we study...
Clocchiatti, Alejandro, Schmidt, Brian P., Filippenko, Alexei V., Challis, Peter, Coil, Alison L., Covarrubias, R., ...
We present observations of the Type I Supernovae (SNe) 1999M, 1999N, 1999Q, 1999S, and 1999U, at redshiftz z ≈ 0.5. They were discovered in early 1999 with the 4.0 m Blanco telescope at Cerro...
Clocchiatti, Alejandro, Schmidt, Brian P., Filippenko, Alexei V., Challis, Peter, Coil, Alison L., Covarrubias, R., ...
We present observations of the Type I Supernovae (SNe) 1999M, 1999N, 1999Q, 1999S, and 1999U, at redshiftz z ≈ 0.5. They were discovered in early 1999 with the 4.0 m Blanco telescope at Cerro...
Weidong Li, Chuanrong Zhang, James E. Burt, A-xing Zhu
ABSTRACT possibility or good guess of soil occurrence in the survey Due to our imperfect knowledge of soil distributions acquired from area. An interpolated map using standard interpolation field...
Two-dimensional Markov chain simulation of soil type spatial distribution (2004)
Weidong Li, Chuanrong Zhang, James E. Burt, Jan Feyen
ABSTRACT At present, such research is still very rare in soil sci-Soils typically exhibit complex spatial variation of multi-categorical variables such as soil types and soil textural classes....
A precise measurement of the [pi]+ [approaches] [pi]0 e+v branching ratio / (2004)
[Pi] in title is the pi symbol.
Asynchronous data communication with low power for gals systems (2002)
Shengxian Zhuang, Weidong Li, Jonas Carlsson, Kent Palmkvist, Lars Wanhammar
Abstract: In this paper, we propose an asynchronous wrapper with new handshake circuits for the data communication in GALS systems. The handshake circuits include two data-ports and a local clock...
An Asynchronous Wrapper with Novel Handshake Circuits for GALS Systems (2002)
Shengxian Zhuang, Weidong Li, Jonas Carlsson, Kent Palmkvist, Lars Wanhammar
Abstract: In this paper, we propose an asynchronous wrapper with novel handshake circuits for data communication to be used in GALS systems. The handshake circuits include two communication ports and...
Modeling and inversion of time domain electromagnetic data / (2002)
Thesis (Ph. D.)--Dept. of Geology and Geophysics, University of Utah, 2002.
A pipeline FFT processor (1999)
Abstract: In this paper, we discuss the design and implementation of a high-speed, low power 1024-point pipeline FFT processor. Key features are flexible internal data length and a novel processing...