Results 41 to 50 of about 6,421 (225)

SN 2021hpr: A Normal Type Ia Supernova Showing Excess Emission in the Early Rising Phase

The Astrophysical Journal
We present extensive optical observations of a nearby Type Ia supernova (SN Ia), SN 2021hpr, located in the spiral galaxy NGC 3147 at a distance of ∼45 Mpc. Our observations cover a phase within ∼1–2 days to ∼290 days after the explosion.
Abdusamatjan Iskandar, Xiaofeng Wang, Ali Esamdin, Xiangyun Zeng, Craig Pellegrino, Shengyu Yan, Jialian Liu, Alexei V. Filippenko, D. Andrew Howell, Curtis McCully, Thomas G. Brink, Maokai Hu, Yi Yang, WeiKang Zheng, Guoliang Lü, Jujia Zhang, CuiYing Song, RuiFeng Huang, Rachael C. Amaro, Chunhai Bai, Kyle G. Dettman, Lluís Galbany, Daichi Hiramatsu, Bostroem K. Azalee, Koichi Itagaki, Saurabh W. Jha, Shuguo Ma, David J. Sand, Jennifer E. Andrews, Jacob Jencson, Peter Milne, Jeniveve Pearson, Manisha Shrestha, Nathan Smith, Réka Könyves-Tóth, Samuel Wyatt, Xuan Zhang, Shahidin Yaqup, Letian Wang, Mengfan Zhang   +39 more
doaj   +1 more source

Near-infrared and Optical Nebular-phase Spectra of Type Ia Supernovae SN 2013aa and SN 2017cbv in NGC 5643

The Astrophysical Journal, 2023
We present multiwavelength time-series spectroscopy of SN 2013aa and SN 2017cbv, two Type Ia supernovae (SNe Ia) on the outskirts of the same host galaxy, NGC 5643. This work utilizes new nebular-phase near-infrared (NIR) spectra obtained by the Carnegie
Sahana Kumar, Eric Y. Hsiao, C. Ashall, M. M. Phillips, N. Morrell, P. Hoeflich, C. R. Burns, L. Galbany, E. Baron, C. Contreras, S. Davis, T. Diamond, F. Förster, M. L. Graham, E. Karamehmetoglu, R. P. Kirshner, B. Koribalski, K. Krisciunas, J. Lu, G. H. Marion, P. J. Pessi, A. L. Piro, M. Shahbandeh, M. D. Stritzinger, N. B. Suntzeff, S. A. Uddin   +25 more
doaj   +1 more source

A Possible Solution to the Mystery of the ANITA Anomalous Events

Annalen der Physik, Volume 538, Issue 4, April 2026.
In 2006 and 2014, the Antarctic Impulsive Transient Antenna (ANITA), a balloon‐borne radio observatory flying over Antarctica, detected two strange upward‐going radio pulse events that have not yet been explained by our current understanding of physics.
Massimo Villata
wiley   +1 more source

The Peculiar Type Ia Supernova 2005hk [PDF]

AIP Conference Proceedings, 2007
We present a preliminary analysis of an extensive set of optical observations of the Type Ia SN 2005hk. We show that the evolution of SN 2005hk closely follows that of the peculiar SN 2002cx. SN 2005hk is more luminous than SN 2002cx, while still under-luminous compared to normal Type Ia supernovae. The spectrum at 9 days before maximum is dominated by
Stanishev, V., Taubenberger, S., Blanc, G., Anupama, G., Benetti, S., Cappellaro, E., Elias-Rosa, N., Féron, C., Goobar, A., Krisciunas, K., Pastorello, A., Sahu, D., Salvo, M., Schmidt, B., Sollerman, J., Thöne, C., Turatto, M., Hillebrandt, W.   +17 more
openaire   +3 more sources

Hitchhiker's Guide to the Swampland: The Cosmologist's Handbook to the String‐Theoretical Swampland Programme

Fortschritte der Physik, Volume 74, Issue 4, April 2026.
Abstract String theory has strong implications for cosmology, implying the absence of a cosmological constant, ruling out single‐field slow‐roll inflation, and that black holes decay. The origins of these statements are elucidated within the string‐theoretical swampland programme.
Kay Lehnert
wiley   +1 more source

Nebular-phase spectra of nearby Type Ia Supernovae

, 2017
We present late-time spectra of eight Type Ia supernovae (SNe Ia) obtained at > 200 d after peak brightness using the Gemini South and Keck telescopes. All of the SNe Ia in our sample were nearby, well separated from their host galaxy's light, and have ...
A. V. Filippenko, M. L. Graham, D. J. Sand, G. Hosseinzadeh, Hosseinzadeh, G., Sand, David J., Parrent, J. T., J. T. Parrent, Graham, M. L., D. A. Howell, D. Hiramatsu, Valenti, S., S. Valenti, I. Arcavi, C. McCully, Hiramatsu, D., Arcavi, I., S. Kumar, Kumar, S., Howell, D. A., McCully, C., Filippenko, A. V.   +21 more
core   +1 more source

OPTICAL SPECTROSCOPY OF TYPE Ia SUPERNOVAE [PDF]

The Astronomical Journal, 2008
We present 432 low-dispersion optical spectra of 32 Type Ia supernovae (SNe Ia) that also have well-calibrated light curves. The coverage ranges from 6 epochs to 36 epochs of spectroscopy. Most of the data were obtained with the 1.5m Tillinghast telescope at the F. L.
Matheson, T., Kirshner, Robert, Challis, Peter, Jha, S., Garnavich, P. M., Berlind, Perry, Calkins, Michael, Blondin, S., Balog, Z., Bragg, A. E., Caldwell, Nelson, Concannon, K. Dendy, Falco, E. E., Graves, G. J. M., Huchra, J. P., Kuraszkiewicz, Joanna, Mader, J. A., Mahdavi, A., Phelps, Matthew, Rines, K., Song, I., Wilkes, Belinda   +21 more
openaire   +4 more sources

Kaniadakis Holographic Dark Energy Behavior in f(Q) Theory

Fortschritte der Physik, Volume 74, Issue 4, April 2026.
ABSTRACT In this study, the cosmological behavior of the Kaniadakis holographic dark energy model is investigated under the f(Q)$f(Q)$ theory within the framework of a flat Friedmann–Robertson–Walker (FRW) universe. The generalized holographic energy density based on Kaniadakis entropy is modeled using the Hubble horizon infrared cutoff scale, and the ...
Sinem Kalkan, Can Aktaş
wiley   +1 more source

Type Ia supernovae as speed sensors at intermediate redshifts

, 2008
Large scale peculiar velocity (LSPV) is a crucial probe of dark matter, dark energy, and gravity at cosmological scales. However, its application is severely limited by measurement obstacles. We show that fluctuations in type Ia supernovae fluxes induced
Chen, Xuelei, Zhang, Pengjie
core   +1 more source

A JWST Medium-resolution MIRI Spectrum and Models of the Type Ia Supernova 2021aefx at +415 days

The Astrophysical Journal
We present a JWST MIRI medium-resolution spectrometer spectrum (5–27 μ m) of the Type Ia supernova (SN Ia) SN 2021aefx at +415 days past B -band maximum.
C. Ashall, P. Hoeflich, E. Baron, M. Shahbandeh, J. M. DerKacy, K. Medler, B. J. Shappee, M. A. Tucker, E. Fereidouni, T. Mera, J. Andrews, D. Baade, K. A. Bostroem, P. J. Brown, C. R. Burns, A. Burrow, A. Cikota, T. de Jaeger, A. Do, Y. Dong, I. Dominguez, O. Fox, L. Galbany, E. Y. Hsiao, K. Krisciunas, B. Khaghani, S. Kumar, J. Lu, J. R. Maund, P. Mazzali, N. Morrell, F. Patat, C. Pfeffer, M. M. Phillips, J. Schmidt, S. Stangl, C. P. Stevens, M. D. Stritzinger, N. B. Suntzeff, C. M. Telesco, L. Wang, Y. Yang   +41 more
doaj   +1 more source