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- Wild, W., et al.
(författare)
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Millimetron—a large Russian-European submillimeter space observatory
- 2009
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Ingår i: Experimental Astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 23:1, s. 221-244
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Tidskriftsartikel (refereegranskat)abstract
- Millimetron is a Russian-led 12 m diameter submillimeter and far-infrared space observatory which is included in the Space Plan of the Russian Federation for launch around 2017. With its large collecting area and state-of-the-art receivers, it will enable unique science and allow at least one order of magnitude improvement with respect to the Herschel Space Observatory. Millimetron will be operated in two basic observing modes: as a single-dish observatory, and as an element of a ground-space very long baseline interferometry (VLBI) system. As single-dish, angular resolutions on the order of 3 to 12 arc sec will be achieved and spectral resolutions of up to a million employing heterodyne techniques. As VLBI antenna, the chosen elliptical orbit will provide extremely large VLBI baselines (beyond 300,000 km) resulting in micro-arc second angular resolution.
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| 2. |
- Bergman, Per, 1960, et al.
(författare)
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Detection of interstellar hydrogen peroxide
- 2011
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 531, s. L8-
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Tidskriftsartikel (refereegranskat)abstract
- Context. The molecular species hydrogen peroxide, HOOH, is likely to be a key ingredient in the oxygen and water chemistry in the interstellar medium. Aims. Our aim with this investigation is to determine how abundant HOOH is in the cloud core rho Oph A. Methods. By observing several transitions of HOOH in the (sub)millimeter regime we seek to identify the molecule and also to determine the excitation conditions through a multilevel excitation analysis. Results. We have detected three spectral lines toward the SM1 position of rho Oph A at velocity-corrected frequencies that coincide very closely with those measured from laboratory spectroscopy of HOOH. A fourth line was detected at the 4 sigma level. We also found through mapping observations that the HOOH emission extends (about 0.05 pc) over the densest part of the rho Oph A cloud core. We derive an abundance of HOOH relative to that of H(2) in the SM1 core of about 1 x 10(-10). Conclusions. To our knowledge, this is the first reported detection of HOOH in the interstellar medium.
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| 3. |
- Ginsburg, A., et al.
(författare)
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Dense gas in the Galactic central molecular zone is warm and heated by turbulence
- 2016
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 586, s. Art nr A50-
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Tidskriftsartikel (refereegranskat)abstract
- Context. The Galactic center is the closest region where we can study star formation under extreme physical conditions like those in high-redshift galaxies. Aims. We measure the temperature of the dense gas in the central molecular zone (CMZ) and examine what drives it. Methods. We mapped the inner 300 pc of the CMZ in the temperature-sensitive J = 3-2 para-formaldehyde (p-H2CO) transitions. We used the 3(2,1)-2(2,0)/3(0,3)-2(0,2) line ratio to determine the gas temperature in n similar to 10(4) - 10(5) cm(-3) gas. We have produced temperature maps and cubes with 30 0 0 and 1 km s(-1) resolution and published all data in FITS form. Results. Dense gas temperatures in the Galactic center range from similar to 60 K to > 100 K in selected regions. The highest gas temperatures T-G > 100 K are observed around the Sgr B2 cores, in the extended Sgr B2 cloud, the 20 km s(-1) and 50 km s(-1) clouds, and in "The Brick" (G0.253 + 0.016). We infer an upper limit on the cosmic ray ionization rate zeta(CR)
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