Extrasolar Visions II
Would you like to react to this message? Create an account in a few clicks or log in to continue.

Extrasolar Visions II

Extrasolar Planets.
 
HomeHome  SearchSearch  Latest imagesLatest images  RegisterRegister  Planet TablePlanet Table  Log in  

 

 Neptune-mass planet at Lam2 Fornacis.

Go down 
3 posters
AuthorMessage
Sirius_Alpha
Admin
Admin
Sirius_Alpha


Number of posts : 4320
Location : Earth
Registration date : 2008-04-06

Neptune-mass planet at Lam2 Fornacis. Empty
PostSubject: Neptune-mass planet at Lam2 Fornacis.   Neptune-mass planet at Lam2 Fornacis. Empty24th February 2009, 10:13 pm

A Neptune-mass Planet Orbiting the Nearby G Dwarf HD16417
http://arxiv.org/abs/0902.4024

Abstract wrote:
Precision Doppler measurements from an intensive 48 night "Rocky Planet Search" observing campaign on the Anglo-Australian Telescope (AAT) have revealed the presence of a low-mass exoplanet orbiting the G1 dwarf HD16417. Subsequent Doppler observations with the AAT, as well as independent observations obtained by the Keck Planet Search, have confirmed this initial detection and refine the orbital parameters to period 17.24+/-0.01 d, eccentricity 0.20+/-0.09, orbital semi-major axis 0.14+/-0.01 AU and minimum planet mass 22.1+/-2.0 Mearth. HD 16417 raises the number of published exoplanets with minimum masses of less than 25 Mearth to eighteen. Interestingly, the distribution of detected sub-25 Mearth planets over the spectral types G, K and M is almost uniform. The detection of HD 16417b by an intensive observing campaign clearly demonstrates the need for extended and contiguous observing campaigns when aiming to detect low-amplitude Doppler planets in short period orbits. Perhaps most critically it demonstrates that the search for low-mass Doppler planets will eventually require these traditional "bright-time" projects to extend throughout dark lunations.

_________________
Caps Lock: Cruise control for 'Cool'!
Back to top Go down
https://solar-flux.forumotion.com/
Edasich
dK star
dK star
Edasich


Number of posts : 2285
Location : Tau Ceti g - Mid Latitudes
Registration date : 2008-06-02

Neptune-mass planet at Lam2 Fornacis. Empty
PostSubject: Re: Neptune-mass planet at Lam2 Fornacis.   Neptune-mass planet at Lam2 Fornacis. Empty25th February 2009, 7:04 am

A hot Neptune from AAT target list.
Now I'm waiting for Epsilon Fornacis. Very Happy
Back to top Go down
Lazarus
dF star
dF star



Number of posts : 3337
Registration date : 2008-06-12

Neptune-mass planet at Lam2 Fornacis. Empty
PostSubject: Re: Neptune-mass planet at Lam2 Fornacis.   Neptune-mass planet at Lam2 Fornacis. Empty25th February 2009, 6:13 pm

From my quick scan of the paper, no mention of transits at all. (I.e. no indication that they've been searched for yet)

Interesting.
Back to top Go down
Edasich
dK star
dK star
Edasich


Number of posts : 2285
Location : Tau Ceti g - Mid Latitudes
Registration date : 2008-06-02

Neptune-mass planet at Lam2 Fornacis. Empty
PostSubject: Re: Neptune-mass planet at Lam2 Fornacis.   Neptune-mass planet at Lam2 Fornacis. Empty26th February 2009, 6:15 pm

Performing a Systemic simulation, there's a strong evidence of additional companion (<0.13 Mj) in 339 days or less orbit.
Back to top Go down
Lazarus
dF star
dF star



Number of posts : 3337
Registration date : 2008-06-12

Neptune-mass planet at Lam2 Fornacis. Empty
PostSubject: Re: Neptune-mass planet at Lam2 Fornacis.   Neptune-mass planet at Lam2 Fornacis. Empty26th February 2009, 6:59 pm

As is said in the paper there is a 289-day periodicity, however the significance is low. Also the eccentricity is suspiciously high: my best fit 2-Keplerian fit has crossing orbits. Using the stability checker on my best 2-planet solution with the second planet's period near 289 days, the inner planet's eccentricity eventually reaches a value where the planet would hit the star at periastron.
Back to top Go down
Sponsored content





Neptune-mass planet at Lam2 Fornacis. Empty
PostSubject: Re: Neptune-mass planet at Lam2 Fornacis.   Neptune-mass planet at Lam2 Fornacis. Empty

Back to top Go down
 
Neptune-mass planet at Lam2 Fornacis.
Back to top 
Page 1 of 1
 Similar topics
-
» GJ 687 b - 38 day Neptune-mass planet
» BD+20 594 b - a Neptune-mass pure rock planet?
» HD 180617 - Nearby binary with Neptune-mass planet near HZ
» Microlensing exoplanet discoveries
» Astrometric detection of Neptune-mass planet at GJ 65 (BL + UV Ceti)

Permissions in this forum:You cannot reply to topics in this forum
Extrasolar Visions II :: Extrasolar Visions :: Extrasolar News and Discoveries-
Jump to: