* Astronomy

Members Login
Username 
 
Password 
    Remember Me  
Home -> Astronomy News -> Stars/galaxy News -> Cygnus X
Post Info TOPIC: Cygnus X
Blobrana


L

Posts: 131433
Date:
Fermi Cygnus Cocoon
Permalink  
 

Title: Suzaku Observation of the Fermi Cygnus Cocoon: Search for a Signature of Young Cosmic-Ray Electrons.
Author: T. Mizuno, T. Tanabe, H. Takahashi, K. Hayashi, R. Yamazaki, I. Grenier, L. Tibaldo

The origin of Galactic cosmic rays remains unconfirmed, but promising candidates for their sources are found in star-forming regions. We report a series of X-ray observations, with Suzaku, toward the nearby star-forming region of Cygnus X. They aim at comparing diffuse X-ray emissions on and off the gamma-ray cocoon of hard cosmic rays revealed by Fermi LAT. After excluding point sources and small-scale structures and subtracting the non-X-ray and cosmic X-ray backgrounds, the 2--10~keV X-ray intensity distribution is found to monotonically decrease with increasing Galactic latitude. This indicates that most of the extended emission detected by Suzaku originates from the Galactic ridge. In two observations, we derive upper limits of 3.4 x 10-8 erg s-1 cm-2 sr-1 and 1.3 x 10-8 erg s-1 cm-2 sr-1 to X-ray emission in the 2--10 keV range from the gamma-ray cocoon. These limits exclude the presence of cosmic-ray electrons with energies above about 50 TeV at a flux level capable of explaining the gamma-ray spectrum. They are consistent with the emission cut-off observed near a TeV in gamma rays. The properties of Galactic ridge and local diffuse X-rays are also discussed.

Read more (2152kb, PDF)



__________________
Blobrana


L

Posts: 131433
Date:
DR21 region
Permalink  
 

DR21 Ridge

DR21_context_annot_small.jpg

This image shows the DR21 ridge, a very massive filamentary structure oriented north-south in the extremely active star-forming region Cygnus X. It resides at a distance of about 4500 light-years from Earth in the constellation of Cygnus, the Swan.
Read more



__________________
Blobrana


L

Posts: 131433
Date:
DR21 ridge
Permalink  
 

Title: The spine of the swan: A Herschel study of the DR21 ridge and filaments in Cygnus X
Authors: M. Hennemann, F. Motte, N. Schneider, P. Didelon, T. Hill, D. Arzoumanian, S. Bontemps, T. Csengeri, Ph. Andre, V. Konyves, F. Louvet, A. Marston, A. Men'shchikov, V. Minier, Q. Nguyen Luong, P. Palmeirim, N. Peretto, M. Sauvage, A. Zavagno, L. D. Anderson, J.-Ph. Bernard, J. Di Francesco, D. Elia, J. Z. Li, P. G. Martin, S. Molinari, S. Pezzuto, D. Russeil, K. L. J. Rygl, E. Schisano, L. Spinoglio, T. Sousbie, D. Ward-Thompson, G. J. White

In order to characterise the cloud structures responsible for the formation of high-mass stars, we present Herschel observations of the DR21 environment. Maps of the column density and dust temperature unveil the structure of the DR21 ridge and several connected filaments. The ridge has column densities larger than 1e23/cm² over a region of 2.3 pc². It shows substructured column density profiles and branching into two major filaments in the north. The masses in the studied filaments range between 130 and 1400 solar masses whereas the mass in the ridge is 15000 solar masses. The accretion of these filaments onto the DR21 ridge, suggested by a previous molecular line study, could provide a continuous mass inflow to the ridge. In contrast to the striations seen in e.g., the Taurus region, these filaments are gravitationally unstable and form cores and protostars. These cores formed in the filaments potentially fall into the ridge. Both inflow and collisions of cores could be important to drive the observed high-mass star formation. The evolutionary gradient of star formation running from DR21 in the south to the northern branching is traced by decreasing dust temperature. This evolution and the ridge structure can be explained by two main filamentary components of the ridge that merged first in the south.

Read more (687kb, PDF)



__________________
Blobrana


L

Posts: 131433
Date:
Cygnus X
Permalink  
 

Cygnus-X: the cool swan glowing in flight

 
Herschel_cygnusX_04052012_Horizontal,1.jpg
 
Herschel's swan

Chaotic networks of dust and gas signpost the next generations of massive stars in this stunning new image of the Cygnus-X star-nursery captured by ESA's Herschel space observatory.
Cygnus-X is an extremely active region of massive-star birth some 4500 light-years from Earth in the constellation of Cygnus, the Swan.

Read more



__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

Before They Were Stars: New Image Shows Space Nursery

The stars we see today weren't always as serene as they appear, floating alone in the dark of night. Most stars, likely including our sun, grew up in cosmic turmoil - as illustrated in a new image from NASA's Spitzer Space Telescope.
The image shows one of the most active and turbulent regions of star birth in our galaxy, a region called Cygnus X. The choppy cloud of gas and dust lies 4,500 light-years away in the constellation Cygnus the Swan. Cygnus X was named by radio astronomers, since it is one of the brightest radio regions in the Milky Way. (It should not be confused with the black hole Cygnus X-1.)
Read more 



__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

Stars Brewing in Cygnus X

A bubbling cauldron of star birth is highlighted in this new image from NASA's Spitzer Space Telescope. Infrared light that we can't see with our eyes has been color-coded, such that the shortest wavelengths are shown in blue and the longest in red. The middle wavelength range is green.
Read more 



__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

Before They Were Stars: New Image Shows Space Nursery

The stars we see today weren't always as serene as they appear, floating alone in the dark of night. Most stars, likely including our own sun, grew up in cosmic turmoil, as illustrated in this new image from NASA's Spitzer Space Telescope.
The image shows one of the most active and turbulent regions of star birth in our Milky Way galaxy, a region called Cygnus X. The choppy cloud of gas and dust lies 4,500 light-years away in the constellation Cygnus or the "Swan." It is home to thousands of massive stars and many more stars around the size of our sun or smaller. Spitzer has captured an infrared view of the entire region, bubbling with star formation.
Read more 



__________________
Page 1 of 1  sorted by
Quick Reply

Please log in to post quick replies.
Home -> Astronomy News -> Stars/galaxy News -> Cygnus X


Create your own FREE Forum
Report Abuse 		Powered by ActiveBoard