Zobrazeno 1 - 10
of 111
pro vyhledávání: '"Jacques P. Vallée"'
Autor:
Jacques P Vallée
Publikováno v:
International Journal of Astronomy and Astrophysics. 12:281-300
To pinpoint the peak location of the synchrotron total intensity emission in a spiral arm, we use a map of the spiralarm locations (from the observed arm tangent). Thus In a typical spiral arm in Galactic Quadrant I, we find the peak of the synchrotr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::abf3a4687f2ff5ee1c8d2e24e8af6f5b
https://doi.org/10.4236/ijaa.2022.124017
https://doi.org/10.4236/ijaa.2022.124017
Autor:
Jacques P Vallée
We compare the observed radial velocity of different arm tracers, taken near the tangent to a spiral arm. A slight difference is predicted by the density wave theory, given the shock predicted at the entrance to the inner spiral arm. In many of these
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ddb9cb08ae286cdb9876a1a0cc493616
Autor:
Jacques P Vallée
An updated catalog of 205 observed tangents to the spiral arms (in Galactic longitudes) since 1980 is presented. This represents an addition of 80 arm tangents in 6 years (since 2016). Most arm tangents are observed at telescopes in the radio regime.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c74e7d0e758f40cb046b2eb8c28159f7
http://arxiv.org/abs/2207.14220
http://arxiv.org/abs/2207.14220
Autor:
Jacques P Vallée
Publikováno v:
Astrophysics and Space Science. 367
Some important predictions from 4 main models of spiral arm formation are tested here, using observational data acquired for the Milky Way galaxy. Many spiral arm models (density wave, tidal wave, nuclear Lyapunov tube, or dynamic transient wave) hav
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2abf4705f699e234f21d6d90cf15e68d
https://doi.org/10.1007/s10509-022-04057-2
https://doi.org/10.1007/s10509-022-04057-2
Autor:
Jacques P. Vallée
We observe the density wave angular pattern speed OMEGA-p to be near 12 to 17 km / s / kpc, by the separation between a typical optical HII region (from the spiral arm dust lane) and using a HII evolution time model to yield its relative speed, and i
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::bf14a4ebe22b9a49ba3c004180d18ff9
Autor:
Jacques P. Vallée
From the Sun, a look at the edge of each spiral arm in our Milky Way (seen tangentially, along the line of sight) can yield numerous insights. Using different arm tracers (dust, masers, synchrotron emission, CO gas, open star clusters), we observe he
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::267306d2f01351fa6acb7e33a2c150cb
Autor:
Jacques P. Vallée
We analyze recent observations of the spiral arm width in the Milky Way, as a function of the galactic radius, and we compare this relation with the prediction from the density wave theory. We use the following method: in each spiral arm, we concentr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e202e10a70fd9ef4fedb34eb435672aa
https://nrc-publications.canada.ca/eng/view/object/?id=a0110c60-6dc3-4aeb-afe9-2b65de4e1ea7
https://nrc-publications.canada.ca/eng/view/object/?id=a0110c60-6dc3-4aeb-afe9-2b65de4e1ea7
Autor:
Jacques P. Vallée
This study extends to the structure of the Galaxy. Our main goal is to focus on the first spiral arm beyond the Perseus arm, often called the Cygnus arm or the Outer Norma arm, by appraising the distributions of the masers near the Cygnus arm. The me
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::304e59014991d847f546719d735ff61a
http://arxiv.org/abs/2004.02054
http://arxiv.org/abs/2004.02054
Statistics on 24 spiral galaxies having different observed arm locations using different arm tracers
Autor:
Jacques P. Vallée
The density wave theory predicted some physical offsets among different tracers of star formation. To test this prediction, here we compiled data on 40 galaxies searched observationally for a physical offset between spiral arm tracers, and found that
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ca9b6cfd481770d3d66fd83dbe5f43dc
https://nrc-publications.canada.ca/eng/view/object/?id=d8b28020-5c4d-44b0-8806-dbba1f2c019c
https://nrc-publications.canada.ca/eng/view/object/?id=d8b28020-5c4d-44b0-8806-dbba1f2c019c
Autor:
Jacques P. Vallée
Some galactic theories of spiral arms predict an offset between different tracers of star formation. Our goal here is to find such an offset between the observed location of radio masers and the location of the arms, using a recent 4-arm model fitted
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::208ef6bee0fb66ee863dab45c1d8e525
https://doi.org/10.1093/mnras/stz2199
https://doi.org/10.1093/mnras/stz2199