Zobrazeno 1 - 10
of 4 260
pro vyhledávání: '"Webb, John"'
Autor:
Milaković, Dinko, Webb, John K., Molaro, Paolo, Lee, Chung-Chi, Jethwa, Prashin, Cupani, Guido, Murphy, Michael T., Welsh, Louise, D'Odorico, Valentina, Cristiani, Stefano, Santos, Ricardo Génova, Martins, Carlos J. A. P., Nunes, Nelson J., Schmidt, Tobias M., Pepe, Francesco A., Osorio, Maria Rosa Zapatero, Alibert, Yann, Hernández, J. I. González, Di Marcantonio, Paolo, Palle, Enric, Santos, Nuno C., Rebolo, Rafael
Chemical evolution models predict a gradual build-up of $^{13}$C in the universe, based on empirical nuclear reaction rates and assumptions on the properties of stellar populations. However, old metal-poor stars within the Galaxy contain more $^{13}$
Externí odkaz:
http://arxiv.org/abs/2407.17953
Autor:
Webb, John K., Lee, Chung-Chi
Searches for spacetime variations of fundamental constants have entered an era of unprecedented precision. New, high quality quasar spectra require increasingly refined analytic methods. In this article, a continuation in a series to establish robust
Externí odkaz:
http://arxiv.org/abs/2401.00887
Autor:
Webb, John K., Lee, Chung-Chi, Milakovic, Dinko, Flambum, Victor V., Dzuba, Vladimir A., Magueijo, Joao
We report unbiased AI measurements of the fine structure constant alpha in two proximate absorption regions in the spectrum of the quasar HE0515-4414. The data are high resolution, high signal to noise, and laser frequency comb calibrated, obtained u
Externí odkaz:
http://arxiv.org/abs/2401.00888
Autor:
Shara, Michael M., Lanzetta, Kenneth M., Garland, James T., Gromoll, Stefan, Valls-Gabaud, David, Walter, Frederick M., Webb, John K., Kniazev, Alexei, Townsend, Lee, Darnley, Matthew J., Healy-Kalesh, Michael, Corral-Santana, Jesus, Schmidtobreick, Linda
Just 10 recurrent novae (RNe) - which erupt repeatedly on timescales shorter than one century - are known in our Galaxy. The most extreme RN known (located in the Andromeda galaxy), M31N 2008-12a, undergoes a nova eruption every year, and is surround
Externí odkaz:
http://arxiv.org/abs/2310.17055
Autor:
Shara, Michael M., Lanzetta, Kenneth M., Garland, James T., Gromoll, Stefan, Valls-Gabaud, David, Walter, Frederick M., Webb, John F., Zurek, David R., Brosch, Noah, Rich, R. Michael
The existence of a vast nova shell surrounding the prototypical dwarf nova Z Camelopardalis (Z Cam) proves that some old novae undergo metamorphosis to appear as dwarf novae thousands of years after a nova eruption. The expansion rates of ancient nov
Externí odkaz:
http://arxiv.org/abs/2310.00123
Autor:
Lanzetta, Kenneth M., Gromoll, Stefan, Shara, Michael M., Berg, Stephen, Garland, James, Mancini, Evan, Valls-Gabaud, David, Walter, Frederick M., Webb, John K.
We used the Condor Array Telescope to obtain deep imaging observations through the luminance filter of the entirety of the NGC 5866 Group, including a very extended region surrounding the galaxy NGC 5907 and its stellar stream. We find that the stell
Externí odkaz:
http://arxiv.org/abs/2309.17248
We propose two neural network based and data-driven supply and demand models to analyze the efficiency, identify service gaps, and determine the significant predictors of demand, in the bus system for the Department of Public Transportation (HDPT) in
Externí odkaz:
http://arxiv.org/abs/2309.06299