Sentences with phrase «hydrogen lines»

Types Ib and Ic are believed to correspond to stars ending their lives (as Type - II supernovae), but such stars would have lost their hydrogen before, and so hydrogen lines don't appear on their spectra (more discussion).

They have even weaker hydrogen lines than F, but along with the ionized metals, they have neutral metals.

Types Ib and Ic are believed to correspond to stars ending their lives (as Type - II supernovae), but such stars would have lost their hydrogen before, and so hydrogen lines don't appear on their spectra (more).

Interference, or «radio noise», even occurs at the wavelength of the famous 21 - centimetre atomic hydrogen line, which many SETI researchers believe another intelligence would logically chose for communication — if such intelligence existed (see «SETI: the search continues», New Scientist, 10 October).

The second fragment, at a distance of ~ 800 astronomical units, is also optically thick to its own cooling radiation from molecular hydrogen lines but is still able to cool via collision - induced emission.

They have strong hydrogen lines, at a maximum by A0, and also lines of ionized metals (Fe II, Mg II, Si II) at a maximum at A5.

Their spectra have neutral helium, which are most prominent at the B2 subclass, and moderate hydrogen lines.

Class W or WR represents the Wolf — Rayet stars, notable for spectra lacking hydrogen lines.

They have extremely weak hydrogen lines, if they are present at all, and mostly neutral metals (Mn I, Fe I, Si I).

In addition, they found that the width of the hydrogen line, which is emitted from cooler gas (with a temperature of about 10,000 K), is broader than the helium line.

«Thanks to the sensitivity and high angular resolution of ALMA we could for the first time detect a rotating disk around a massive star and effects of electric fields on the hydrogen line emission from a jet from the same star», added Lars Nyman, Head of Science Operations at the JAO ALMA Observatory and co-author of the study.

Their spectra are characterized by the weaker hydrogen lines and ionized metals.

Andrew Siemion, director of the Berkeley SETI Research Center, says that a wider radio search beyond the so - called «hydrogen line» (which is where the most abundant element in the universe «broadcasts,» and is a smart bet for finding stray radio signals) will require more computing power.

Its spectrum contains lines of ionized and neutral metals, as well as very weak hydrogen lines.

Types Ib and Ic are believed to correspond to stars ending their lives (as Type - II supernovae), but such stars would have lost their hydrogen before, and so their hydrogen lines don't appear on their spectra (more).