Qatar Exoplanet Survey (QES) News and Results

Space.com reports the discovery of Qatar-1 b, a 1.2 R_J, 1.1 M_J planet transiting a K-type star every 1.4 d.

Does anyone know anything more... official?

Edit: Found the team's website.

They also talk about WASP-36 and WASP-39 b, yet unreleased.

Qatar-1b: a hot Jupiter orbiting a metal-rich K dwarf star
http://arxiv.org/abs/1012.3027

Quote :

We report the discovery and initial characterisation of Qatar-1b, a hot Jupiter orbiting a metal-rich K dwarf star, the first planet discovered by the Alsubai Project exoplanet transit survey. We describe the strategy used to select candidate transiting planets from photometry generated by the Alsubai Project instrument. We examine the rate of astrophysical and other false positives found during the spectroscopic reconnaissance of the initial batch of candidates. A simultaneous fit to the follow-up radial velocities and photometry of Qatar-1b yield a planetary mass of 1.09+/-0.08 Mjup and a radius of 1.16+/-0.05 Rjup. The orbital period and separation are 1.420033 days and 0.0234 AU for an orbit assumed to be circular. The stellar density, effective temperature and rotation rate indicate an age greater than 4 Gyr for the system.

http://dp2tvgkazihno.cloudfront.net/app/media/2677

http://www.qatarsocial.com/thread-6325-1-1.html

It is published on this magazine, but apparently yet not on scientific paper.

They mention Qatar-2 c as having Earth-like properties. Two options: either Kepler team has been defeated in time or we quite need to have some scientific data to verify. I am for the latter...

Jupiter size with earth like composition very weird for me

Don't take too much from the magazine. It's quite likely that there's a lot of translation issues in the article, such as claiming Venus was discovered in 1970.

I would say that what Qatar-2c more likely represents is a habitable-zone Jupiter. Very exciting, but not as exciting as a habitable-zone Earth.

http://www.abstractsonline.com/plan/ViewAbstract.aspx?mID=2883&sKey=31d177a4-c1d5-4b29-a40a-fc91571626b5&cKey=5da5d8e2-b6d9-4235-8a16-aa89fb98188c&mKey={25369F54-5CB0-4639-BC20-B20273090B9A}

Link to the abstract for the paper.

Short-period transiting hot Jupiter, longer period but somewhat unconstrained Jovian planet in an orbit with a period "slightly less than a year."

Edit: now on arXiv.
http://arxiv.org/abs/1110.5912

Physical properties, starspot activity, orbital obliquity, and transmission spectrum of the Qatar-2 planetary system from multi-colour photometry
http://arxiv.org/abs/1406.6714

Edasich wrote:

http://dp2tvgkazihno.cloudfront.net/app/media/2677

http://www.qatarsocial.com/thread-6325-1-1.html

It is published on this magazine, but apparently yet not on scientific paper.

They mention Qatar-2 c as having Earth-like properties. Two options: either Kepler team has been defeated in time or we quite need to have some scientific data to verify. I am for the latter...

Neither of the links work.

That would probably be because they're three years old…

Indeed...

There are several ArXiv preprints about Qatar-2, ain't it?

They have taken some time but finally some update from "Qatar Survey".

Qatar Exoplanet Survey : Qatar-3b, Qatar-4b and Qatar-5b

Quote :

We report the discovery of Qatar-3b, Qatar-4b, and Qatar-5b, three new transiting planets identified by the Qatar Exoplanet Survey (QES). The three planets belong to the hot Jupiter family, with orbital periods of PQ3b=2.5079204 days, PQ4b=1.8053949 days, and PQ5b=2.8792319 days. Follow-up spectroscopic observations reveal the masses of the planets to be MQ3b=4.31MJ, MQ4b=5.85MJ, and MQ5b=4.32MJ, while model fits to the transit light curves yield radii of RQ3b=1.096RJ, RQ4b=1.552RJ, and RQ5b=1.107RJ. No evidence of eccentric orbit is seen in the radial velocity curve of any of the planets. The host stars are typical main sequence stars with masses and radii MQ3=1.145M⊙, MQ4=0.954M⊙, MQ5=1.128M⊙ and RQ3=1.272R⊙, RQ4=1.115R⊙ and RQ5=1.076R⊙ for the Qatar-3, 4 and 5 respectively. All three new planets can be classified as heavy hot Jupiters (M > 4 MJ), while Qatar-5 is among the most metal-rich stars known to host a planet.

I'm surprised about Qatar-4b's inflated radius and total lack of stellar coordinates for exoplanet host stars.

Yeap, no coordinates, no cross-references to other star catalogues. From the information given in the paper, follow-up observations are not possible.

I noticed that, too. Very frustrating. How do we know these Qatar-# planets aren't already discovered by SuperWASP or HATNet?

May be we should put all Qatar planets in the unconfirmed section.

I contacted Dr. Khalid A. Al-Subai about an hour ago regarding RA and Dec coordinates and within 30 minutes he got back to me. He said they'll post a revision on arXiv with RA and Dec coordinates "soon."

One "soon" later and there's still nothing, right?

Anyway, concerning a star we know how to locate:

Recurring sets of recurring starspots on exoplanet-host Qatar-2

Quote :

We announce the detection of recurring sets of recurring starspot occultation events in the short-cadence K2 lightcurve of Qatar-2, a K dwarf star transited every 1.34 d by a hot Jupiter. In total we detect 30 individual starspot occultation events, 28 of which form nine sets of recurring events with the longest set consisting of five occultation events in consecutive transits. Moreover, three sets of spot occultations were found to be from the same starspot over two full stellar rotations, setting a minimum starspot lifetime to 40 d. Another starspot reappeared after one stellar rotation. Starspot analysis provided a robust stellar rotational period measurement of 18.0 ± 0.1 d and indicates that the system is aligned, having an obliquity of 0 ± 8°. A pronounced rotational modulation in the lightcurve has a period of 18.2 ± 1.6 d, in agreement with the rotational period derived from the starspot occultations. We tentatively detect an ellipsoidal modulation in the phase-curve, with a semi-amplitude of 18 ppm, but cannot exclude the possibility that this is the result of red noise or imperfect removal of the rotational modulation. We detect no transit-timing and transit-duration variations with upper limits of 15 s and 1 min, respectively. We also reject any additional transiting planets with transit depths above 330 ppm in the orbital period region 0.5-30 d.

See also Mancini et al. (2014), who carried out something similar with ground-based photometry.

Also, it appears that a spectroscopic paper of some sort is coming in future:

Quote :

A slower rotation than previously thought is further supported by the latest measurements of projected rotational velocity which place it at 2.1 ± 0.6 km s^-1 (Esposito et al., in prep)

Third draft of discovery paper with coordinates added. The all of the exoplanets are located in Andromeda.

I'm having a hard time figuring out which stars these are, which seems odd given their brightnesses. I put the coordinates in SIMBAD and nothing shows up that matches the parameters of the Qatar-# star within several arcmin.

From what I can tell, Qatar-3 is the star below and just to the right of the diffraction spike in the DSS image of HD 224302.

Given the relationships in Jordi et al. (2010), the G-magnitude for Qatar-3 should be approximately 12.65. The closest match I find in the Gaia DR1 catalogue is source 2878641357005625728, which has G-magnitude 12.71 and seems to be in roughly the right position.

Qatar-4 (predicted G-magnitude 13.19) looks likely to be Gaia source 385697168511494656 with G-magnitude 13.316.

Qatar-5 (predicted G-magnitude 12.30) looks likely to be Gaia source 382111248777193216 with G-magnitude 12.434.

None of the three Gaia sources is in the TYC2 catalogue (likely too faint), so have no parallaxes in Gaia DR1. I don't see any evidence for them being in SIMBAD either, for the time being.

I received an email from a G.D. Nordley with the following information. (posted with permission)

Qatar-3
UCAC3-253-304972
2MASS J23563647+3612466
USNO-B1.0 1262-0552146
GSC1 2780-01346
mB 13.13 Alsubai+16
mV 12.88 Alsubai+16
mR 13.2 2MASS
mI 11.46 USNO
mJ 11.601 2MASS
mH 11.272 2MASS
mK 11.219 2MASS

Qatar-4
UCAC3-269-003518
2MASS J00192622+4401395
USNO-B1.0 1340-0006384
GSC1 2794-01333
mB 14.69 Alsubai+16
mV 13.6 Alsubai+16
mR 13.3 2MASS
mI 12.23 USNO
mJ 12.030 2MASS
mH 11.631 2MASS
mK 11.519 2MASS

Qatar-5
UCAC3 265-004681
2MASS J00281293+4203407
USNO-B1.0 1320-0009215
GSC1 2791-02249
mB 13.69 Alsubai+16
mV 12.8 Alsubai+16
mR 12.5 2MASS
mI 11.49 USNO
mJ 11.348 2MASS
mH 11.089 2MASS
mK 10.956 2MASS

In principle that could be used to check the Gaia IDs I posted earlier, but VizieR query functionality doesn't seem to work very well with the full Gaia dataset, and I have no other reason to download such huge datafiles.

I have seen on the EPE that these new Qatar coordinates are validated by VIzier.

Qatar Exoplanet Survey: Qatar-6b -- a grazing transiting hot Jupiter
https://arxiv.org/abs/1712.03216

Quote :

We report the discovery of Qatar-6b, a new transiting planet identified by the Qatar Exoplanet Survey (QES). The planet orbits a relatively bright (V=11.44), early-K main-sequence star at an orbital period of P~3.506 days. An SED fit to available multi-band photometry, ranging from the near-UV to the mid-IR, yields a distance of d = 101 +/- 6 pc to the system. From a global fit to follow-up photometric and spectroscopic observations, we calculate the mass and radius of the planet to be Mp = 0.67 +/- 0.07 Mjup and Rp = 1.06 +/- 0.07 Rjup, respectively. We use multi-color photometric light curves to show that the transit is grazing, making Qatar-6b one of the few exoplanets known in a grazing transit configuration. It adds to the short list of targets that offer the best opportunity to look for additional bodies in the host planetary system through variations in the transit impact factor and duration.