High cadence near infrared timing observations of extrasolar planets

Free access article

Issue		A&A Volume 507, Number 1, November III 2009


Page(s)		481 - 486
Section		Planets and planetary systems
DOI		http://dx.doi.org/10.1051/0004-6361/200810908
Published online		27 August 2009

A&A 507, 481-486 (2009)
DOI: 10.1051/0004-6361/200810908

I. GJ 436b and XO-1b

C. Cáceres^{1, 2}, V. D. Ivanov², D. Minniti^{1, 3}, D. Naef², C. Melo², E. Mason², F. Selman², and G. Pietrzynski⁴

¹ P. Universidad Católica de Chile, Departamento de Astronomía y Astrofísica, Casilla 306, Santiago 22, Chile
e-mail: cccacere@astro.puc.cl
² European Southern Observatory, Av. Alonso de Cordova 3107, Santiago 19001, Chile
³ Specola Vaticana, V00120 Vatican City State, Italy
⁴ Departamento of Astronomía, Universidad de Concepción, Casilla 160-C, Concepción, Chile

Received 3 September 2008 / Accepted 5 May 2009

Abstract
Currently the only technique sensitive to Earth mass planets around nearby stars (that are too close for microlensing) is the monitoring of the transit time variations. We search for additional planets in the systems of the hot Neptune GJ 436b, and the hot-Jupiter XO-1b, using high cadence observations in the J and $K_{\rm S}$ bands. New high-precision transit timing measurements are reported: GJ 436b $T_{\rm C}$ = 2 454 238.47898 $\pm$ 0.00046 HJD; XO-1b $T_{\rm C}$ (A) = 2 454 218.83331 $\pm$ 0.00114 HJD, $T_{\rm C}$ (B) = 2 454 222.77539 $\pm$ 0.00036 HJD, $T_{\rm C}$ (C) = 2 454 222.77597 $\pm$ 0.00039 HJD, $T_{\rm C}$ (D) = 2 454 226.71769 $\pm$ 0.00034 HJD, and they were used to derive new ephemeris values. We also determined depths for these transits. No statistically significant timing deviations were detected. We demonstrate that the high cadence, ground based near-infrared observations are successful in constraining the mean transit time to ~30 s, and are a viable alternative to space missions.

Key words: stars: planetary systems -- stars: individual: GJ 436 -- methods: observational -- stars: individual: XO-1b

What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.

If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.