Results 171 to 180 of about 453,375 (273)

On powers of the diophantine function $\star:x\mapsto x(x+1)$ [PDF]

arXiv
We treat the functions $\star^k:{\mathbf N}\rightarrow{\mathbf N}$ where $\star:x\mapsto \star x := x(x+1)$. The set $\{\star^k x+1: \{x,k\}\subseteq{\mathbf N}\}$ is pairwise coprime; so, the set ${\mathbf P}$ of primes is infinite. Our Theorem 4 resorts to the mother sequence, M, that is obtained by factoring the infinite sequence $2,3,4,5,\ldots ...
arxiv  

Luminosity jumps in pre-main-sequence stars

The Astrophysical Journal, 1989
Thermal relaxation in young stars is discussed, showing how luminosity jumps occur in those of sufficient mass. The essential character of the thermal relaxation process is shown to be internal heat transfer accompanied by nonhomologous contraction.
openaire   +2 more sources

iSHELL K-band Survey of Class I and Flat Spectrum Sources: Magnetic Field Measurements in the Protostellar Phase

The Astrophysical Journal
We perform the first magnetic field strength survey of Class I and Flat Spectrum (FS) sources using K -band observations with iSHELL. We obtained new observations of 42 Class I and FS sources and additionally included 10 sources from the archive.
C. Flores, M. S. Connelley, B. Reipurth, A. Boogert, G. Doppmann   +4 more
doaj   +1 more source

EXPORT: Near-IR observations of Vega-type and pre-main sequence stars [PDF]

, 2001
C. Eiroa, F. Garzón, A. Alberdi, D. de Winter, R. Ferlet, C. A. Grady, A. Collier Cameron, J. K. Davies, H. J. Deeg, A. W. Harris, K. Horne, B. Merín, L. F. Miranda, B. Montesinos, A. Mora, R. D. Oudmaijer, J. Palacios, A. J. Penny, A. Quirrenbach, H. Rauer, Jean Schneider, E. Solano, Y. Tsapras, P. R. Wesselius   +23 more
openalex   +1 more source

Dracula’s Chivito: Discovery of a Large Edge-on Protoplanetary Disk with Pan-STARRS

The Astrophysical Journal Letters
We report the serendipitous discovery of a large edge-on protoplanetary disk in Pan-STARRS (PS1) images. PS1 has five broadband filters designated as g _P1 , r _P1 , i _P1 , z _P1 , and y _P1 with mean wavelengths 4866, 6215, 7545, 8679, and 9633 Å ...
Ciprian T. Berghea, Ammar Bayyari, Michael L. Sitko, Jeremy J. Drake, Ana Mosquera, Cecilia Garraffo, Thomas Petit, Ray W. Russell, Korash D. Assani   +8 more
doaj   +1 more source

Accretion onto Pre-Main Sequence Binary Stars: The Circumstellar Environment [PDF]

, 2001
Robert D. Mathieu
openalex   +1 more source

Circumstellar Disks in pre-Main Sequence Stars

, 2003
This review covers the properties of disks around pre-main--sequence stars. It is at this time in the evolution that planets form, and it is important to understand the properties of these disks to understand planet formation. I discuss disk shapes, masses and temperatures, the properties of the host stars, disk lifetimes and dissipation processes ...
openaire   +2 more sources

Spin-down of Solar-mass Protostars in Magnetospheric Accretion Paradigm

The Astrophysical Journal
Stellar spin is one of the fundamental quantities that characterize a star itself and its planetary system. Nevertheless, stellar spin-down mechanisms in protostellar and pre-main-sequence stellar phases have been a long-standing problem in star ...
Shinsuke Takasao, Masanobu Kunitomo, Takeru K. Suzuki, Kazunari Iwasaki, Kengo Tomida   +4 more
doaj   +1 more source

A spectro-astrometric study of southern pre-main sequence stars [PDF]

, 2002
M. Takami, Jeremy Bailey, A. Chrysostomou   +2 more
openalex   +1 more source

SPYGLASS. V. Spatially and Temporally Structured Star-forming Environments in the Cepheus-Hercules Complex

The Astrophysical Journal
Young associations record complete histories of star-forming events through their demographics and dynamics, and Gaia has greatly expanded our knowledge of these associations.
Ronan Kerr, Adam L. Kraus, Daniel Krolikowski, Luke G. Bouma, Juan P. Farias   +4 more
doaj   +1 more source