1. The APACHE Project:
searching for transiting planets around cool stars
Mario Damasso
OAVdA & Dept. of Physics and Astronomy (University of Padova)
on behalf of the APACHE team

2. Introducing APACHE
 APACHE stands for
A PAthway toward the Characterization of Habitable Earths
 It is a long-term targeted, small field photometric survey aimed at discovering
transiting small-size exoplanets around a well-defined sample of hundreds of
nearby dM0-dM5 stars, using an array of 400-mm telescopes
complementary to the MEarth survey
 The APACHE photometric database will greatly contribute to the astrophysics
of the M dwarfs, throught the characterization of their micro variability (rotation,
activity)
Two telescopes founded by Cassa di Risparmio di Torino

3. The primary node
The Astronomical Observatory of the Autonomous Region of Aosta Valley (OAVdA)
A detailed feasibility study has been carried out to demonstrate that the OAVdA
is a well-poised site where this long-term survey can be based (Damasso et al., PASP, 2010).

4. The APACHE Team
The OAVdA team The INAF-OATo team
Enzo Bertolini Luciano Lanteri
Andrea Bernagozzi Mario G. Lattanzi
Paolo Calcidese Richard Smart
Albino Carbognani Alessandro Sozzetti (P.I.)
Davide Cenadelli
Jean Marc Christille
Mario Damasso
Paolo Giacobbe

5. Milestones of the APACHE Project
A site characterization/feasibility study in 2009
(Damasso et al., PASP, 2010)
A pilot study in 2010 and part of 2011
(Giacobbe et al., MNRAS, 2012)
The long-term photometric survey

6. The pilot study
We presented the results of a 1.5 year-long photometric monitoring campaign of a
sample of 23 nearby (d < 60 pc), bright (J < 12) dM stars.
This survey has been carried out with the pre-existing instrumentation
and was planned as a necessary training for the definition and fine tuning
of the APACHE survey.
2010 NOW

7. Sensitivity to transits 0.5 < P < 5 days
(planets of given radius and period)
0.5 < P < 1 day
1-2.2 R
Starting from our real data, we simulated:
a) 1000 random, uniformly distributed periods
in the range 0.5 – 5 days
b) 100 random, uniformly distributed phases
for each period
c) 4 amplitudes of transit signal depth
(2%, 1.5%, 1% and 0.5%)  0.8-4.5 R
400,000 light curves/target

8. The Apaches
Four 400-mm telescopes are
installed and functioning
Telescope:
RC Pro 400 LT f/8.4
Weight: 42 kg
Optical set glass: LK7 for LT model
Mount:
GM 2000 - QCI, 10 Micron
CCD:
Fli PROLINE KAF-1001°
Array Size: 1024 x 1024
Pixel size: 24 μm
Pixel scale 1.5 arcsec/pixel
Field: 26.3' X 26.3'

9. Preparing to the survey…
The telescope automatic
control system
The APACHE input catalogue

10. The observing strategy
Credit: Giovanni Antico (www.gantico.com)

11. Pipelines for data reduction and analysis
Real-time photometry Post-observations photometry
Two independent pipelines
TSE – Transit SEntinel
TEEPEE Robin
 Intra-night ensemble differential photometry
 Multi-epoch differential photometry (stellar rotation)
 Automatic search for transit-like signals
 Discovery and first characterization of new
variable stars
Intra-night ensemble differential photometry

12. Preliminary results
targets with small intra-night RMS
Nights of observation (since July, 9): 73
Number of different fields observed: 93
Mean number of fields per telescope per night (in winter): 12 time
time time
time

13. Preliminary results
a close eclipsing binary star
Reported in ASAS photometry ROSAT sources. I.
(Acta Astronomica vol. 62, 67-95, March 2012)
Secondary minimum (2012/10/24)
time
Original data from the telescope APACHE#1
Follow-up with the 810-mm telescope
in OAVdA
V=12.4 (APASS)
dM0, H-alpha emission (Riaz
et al., 2006)
X-ray emission (ROSAT)
Orbital period: 0.5667 days
Evidence for spots?
Primary minimum (2012/10/22)

14. Preliminary results tha
n this
!
new variable stars m ore
d
...an
CzeV188
EW, P = 0.247 days VSX J214004.5+273835
EW, P = 0.289 days
VSX J194934.6+314713
GSC 04463-01592 EA, P = 0.523 days
EB, P = 0.642 days
>

15. For more details about the design and the
status of the survey see Christille et al. poster!

16. Support observations
the Asiago Red Dwarf Survey (ARDS)

17. The GAPS observational program
(see the Claudi’s talk of yesterday)
One of the goals of GAPS is the determination of the frequency of potentially habitable
low-mass planets for the nothern low-mass stars.
Some of the GAPS targets have been selected from the APACHE catalogue, and
those targets have been assigned the highest priority in the APACHE schedule.
RV and photometric data are collected during the same period and, if the sky
collaborates, also during the same nights.

18. The APACHE-Gaia synergy
For a typical target with V~14 at d~20 pc, Gaia will provide parallaxes with σ(π)/π~0.1%!
A precise characterization of the host star fundamental parameters for a precise knowledge
of the planet bulk properties (e.g. “GJ 1214 reviewed”, Anglada-Escudé et al., A&A submitted)
Precise measurements of the trigonometric parallax for the APACHE targets imply:
 Their intrinsic luminosity, mass and radius could be significantly updated
 Improved metallicities using photometric methods
For bright targets with transiting planets, these updated values for the host stars (especially
the radius) imply a precise determination of the planet radius. Combined with exquisite RV
data (e.g. HARPS-N), the density of the planet can be precisely determined.

19. http://apacheproject.altervista.org/

20. THANKS FOR
YOUR ATTENTION

21. V mag distribution of the APACHE targets
~12.5-13