Results 11 to 20 of about 10,963 (195)

How rotation affects masses and ages of classical Cepheids

EPJ Web of Conferences, 2017
Classical Cepheid variable stars are both sensitive astrophysical laboratories and accurate cosmic distance tracers. We have recently investigated how the evolutionary effects of rotation impact the properties of these important stars and here provide an
Anderson Richard I., Ekström Sylvia, Georgy Cyril, Meynet Georges, Saio Hideyuki   +4 more
doaj   +2 more sources

Toward a renewed Galactic Cepheid distance scale from Gaia and optical interferometry [PDF]

EPJ Web of Conferences, 2017
Through an innovative combination of multiple observing techniques and modeling, we are assembling a comprehensive understanding of the pulsation and close environment of Cepheids.
Kervella Pierre, Mérand Antoine, Gallenne Alexandre, Trahin Boris, Nardetto Nicolas, Anderson Richard I., Breitfelder Joanne, Szabados Laszlo, Bond Howard E., Borgniet Simon, Gieren Wolfgang, Pietrzyński Grzegorz   +11 more
doaj   +2 more sources

Point-of-care nucleic acid testing - a step forward in controlling the HIV epidemic: A review. [PDF]

HIV Med
Abstract Introduction The HIV/AIDS epidemic, with 85.6 million infections and 40.4 million AIDS‐related deaths globally, remains a critical public health challenge. Current diagnostic methods, primarily fourth‐generation immunoassays, have limitations due to their long window periods, and most viral load assays require centralized testing protocols ...
Pinar SS, Manak M, Saravanan S, Imami N, Kibirige C.   +4 more
europepmc   +2 more sources

The Araucaria Project. First Cepheid Distance to the Sculptor Group Galaxy NGC 7793 from Variables discovered in a Wide-Field Imaging Survey [PDF]

, 2010
We have detected, for the first time, Cepheid variables in the Sculptor Group spiral galaxy NGC 7793. From wide-field images obtained in the optical V and I bands on 56 nights in 2003-2005, we have discovered 17 long-period (24-62 days) Cepheids whose ...
Alejandro Garcia-Varela, Alistair Walker, Andrzej Udalski, Bono, Bresolin, Fabio Bresolin, Freedman, Garcia, Gieren, Gieren, Gieren, Gieren, Giuliano Pignata, Grzegorz Pietrzyński, Igor Soszyński, Jacobs, Jerjen, Kudritzki, Marcin Kubiak, Mario Hamuy, Michał Szymański, Olaf Szewczyk, Pascal Fouqué, Persson, Pietrzyński, Pietrzyński, Pietrzyński, Pietrzyński, Pietrzyński, Rolf-Peter Kudritzki, Sandage, Schlegel, Schwarzenberg-Czerny, Soszyński, Tully, Udalski, Udalski, Udalski, Urbaneja, Wolfgang Gieren, Woźniak, Łukasz Wyrzykowski   +41 more
core   +3 more sources

MOND rotation curves for spiral galaxies with Cepheid-based distances [PDF]

, 2002
Rotation curves for four spiral galaxies with recently determined Cepheid-based distances are reconsidered in terms of modified Newtonian dynamics (MOND). For two of the objects, NGC 2403 and NGC 7331, the rotation curves predicted by MOND are compatible
Bottema, Roelof, Pestana, Jose L. G., Rothberg, Barry, Sanders, Robert H.   +3 more
core   +2 more sources

A revised Cepheid distance to NGC 4258 and a test of the distance scale [PDF]

, 2000
In a previous paper (Maoz et al. 1999), we reported a Hubble Space Telescope (HST) Cepheid distance to the galaxy NGC 4258 obtained using the calibrations and methods then standard for the Key Project on the Extragalactic Distance Scale.
Alibert Y., Barry F. Madore, Eyal Maoz, Ferrarese L., Greenhill L. J., Jeffrey A. Newman, Laura Ferrarese, Maoz E., Marc Davis, Nevalainen J., Peter B. Stetson, Sasselov D. D., Stephen E. Zepf, Udalski A., Wendy L. Freedman   +14 more
core   +2 more sources

Calibration of the Distance Scale from Cepheids [PDF]

, 2002
We have used the infrared surface brightness technique to obtain a new absolute calibration of the Cepheid PL relation in optical and near-infrared bands from improved data on Galactic stars.
Fouque, Pascal, Gieren, Wolfgang, Storm, Jesper   +2 more
core   +4 more sources

Reconciliation of the Surface Brightness Fluctuations and Type Ia Supernovae Distance Scales [PDF]

, 2001
We present Hubble Space Telescope measurements of surface brightness fluctuations (SBF) distances to early-type galaxies that have hosted Type Ia supernovae (SNIa).
Ajhar, Edward A., Blakeslee, John P., Riess, Adam G., Schmidt, Brian P., Tonry, John L.   +4 more
core   +3 more sources

The extra-galactic Cepheid distance scale from LMC and Galactic period-luminosity relations [PDF]

, 2003
In this paper, we recalibrate the Cepheid distance to some nearby galaxies observed by the HST Key Project and the Sandage-Tammann-Saha group. We use much of the Key Project methodology in our analysis but apply new techniques, based on Fourier methods ...
Beaulieu, Beaulieu, Buchler, C. Ngeow, Caputo, Cardelli, Feast, Feast, Feast, Feast, Ferrarese, Freedman, Freedman, Freedman, Freedman, Gibson, Gibson, Gieren, Gould, Groenewegen, Groenewegen, Herrnstein, Hill, Holtzman, Kanbur, Kelson, Kennicutt, Kennicutt, Kochanek, Labhardt, Lanoix, Lanoix, Leonard, M. A. Hendry, Macri, Madore, Madore, Moffett, Moffett, Mould, N. R. Tanvir, Newman, Ngeow, Paturel, Paturel, Paturel, S. M. Kanbur, S. Nikolaev, Saha, Saha, Saha, Saha, Saha, Sandage, Sandage, Sasselov, Schechter, Sebo, Silbermann, Simon, Spergel, Stetson, Stetson, Stetson, Stetson, Stetson, Tammann, Tammann, Tanvir, Thim, Udalski, Udalski, Willick   +72 more
core   +2 more sources

Crowded No More: The Accuracy of the Hubble Constant Tested with High-resolution Observations of Cepheids by JWST

The Astrophysical Journal Letters, 2023
High-resolution James Webb Space Telescope (JWST) observations can test confusion-limited Hubble Space Telescope (HST) observations for a photometric bias that could affect extragalactic Cepheids and the determination of the Hubble constant.
Adam G. Riess, Gagandeep S. Anand, Wenlong Yuan, Stefano Casertano, Andrew Dolphin, Lucas M. Macri, Louise Breuval, Dan Scolnic, Marshall Perrin, Richard I. Anderson   +9 more
doaj   +1 more source