Download Kuchnig_CW8 - Sciences et techniques

MOST - COROT/CW8
MOST MISSION
• status summary
• recent targets and results
• updates, news
• upcoming schedule and targets
The MOST Science Team
presented by Rainer Kuschnig
COROT/CW8 - MOST - May-05 - Toulouse
MOST Main Features
> 15 cm Maksutov Telescope
> 3 arcsec/pixel
> micro-satellite bus 50kg, 60x60x25cm
> Science and Star Tracker CCD (1kx1k, 13um)
> LEO 820 km sun synchronous dawn/dusk orbit
> Science Imaging/Data:
primary:
Fabry (Pupil) image via micro lens
transfer optics - 1400 pixels exposed
secondary: Direct image - PSF FWHM ~2.0pix
Guide Star Signals submitted as well
> Exposure times: 0.5 to 60 sec (0.5-1.6 Guide stars)
> Broadband custom filter 380 ≤ λ ≤ 750 nm
> CCD temp -36 to - 40C stable to 0.1deg over an orbit
> CVZ -18 < dec < +38 and sun sensor limits
> maximum possible observation time base 50 days
> 3 ground stations Toronto, Vancouver, Vienna
> 14.5 Mb bandwidth Science data & Telemetry
COROT/CW8 - MOST - May-05 - Toulouse
MOST - what was done so far
695 days in space ~ 23 month
504 days after commissioning ~ 17 month
Number of observing runs:
19: Procyon-04,beta Vir,eta Boo-04,tau Boo-04,zeta Oph,
WR123,gam Equ,HD209458,51 Peg, PG0101+039,kap1Ceti-04,
HR1217,NGC2264 (2 targ.),Procyon-05,iota Leo,beta Com,
eta Boo-05,tau Boo-05,eps Oph (just started)
+
4: commissioning targets - delta Ceti, kap1Ceti-03,Aldeberan, xi Gem
+
4: test observations - M67,2 asteroids, misc,
Observing length: 9 to 48 days - typically 28 days
COROT/CW8 - MOST - May-05 - Toulouse
MOST - instrumental aging
MOST is almost 2 years in space passing the SAA about
6 times per day and went through 2 periods of high solar
activity
• warm/hot pixel increase from 0.5% after launch about ~2%
after 8 month and about 6% after 20 month
• no degradation of solar cells - power production
• number of crashes has stayed level ~ once every 5 week
>90% occurred during SAA passage
!!!! Watch closely during
WEEKENDs !!!!
MOST is healthy! Up to date no performance degradation
of any significance has happened concerning the instrument
or other vital subsystems like ACS, or Power
COROT/CW8 - MOST - May-05 - Toulouse
MOST - observing after CW7
Targets and observations after the last COROT Week (7)
• NGC 2264 - main targets 2 know PMS stars
• Procyon - follow up with better pointing
• iota Leo - search for Solar-type p-modes
• beta Com - short preview run spot structure/p-modes
• eta Boo - follow up for consistency check
• tau Boo - follow up on orbital/rotation signatures seen
in 2004
• eps Oph - red Giant p-mode investigation
(just started…)
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC 2264
Target Type: 2 known PMS variable stars were the main targets
in direct imaging mode, 15 Mon a bright O star was observed as a
secondary target on a Fabry Lens and 27 other stars (majority are reported
cluster members) in the direct imaging and guide star field
Goals: search for additional (prev. unresolved) pulsation modes of the
2 PMS variables, check for frequency shifts and probe all other stars for
including 15 Mon for variability of any nature
Observing Dates: 6-Dec-2004 to 24-Jan02005 - 48 days
longest run conducted with MOST thus far
Status: data reduction completed, PMS photometry analysis underway
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
V589 Mon
15 Mon
V588 Mon
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
15 Mon = S Mon is a spectroscopic binary [Doug Gies et al. 1993, 1997]
A O7 V (f) 34 MSUN
B O9.5 Vn 19 MSUN vsini ~ 350 km/s ΔV~1.2
forb- f1
114.83 min or 12.55 c/d
Frequency [c/d]
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
Stars within 30 asec of 15 Mon from
Washington Visual Double Star Catalog
asec Amag Bmag
4 possible variables:
1 AB
3.8
9.30
10.40
15 Mon A - 115 min period 5x10-4 variation
3 Aa
0.1
4.66
(5.9)
15 Mon Ab - amplitude ~ 1.5x10-3
4 Aa-B
2.8
4.80
7.60
STF950 Aa-B - amplitude ~ 7x10-3
5 Aa-C
16.6
4.70
9.90
one of the other stars - amplitude ~5x10-2
16
14.2
17 AB
14.0
9.95
10.10
20 AB
2.6
9.80
10.30
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
COROT/CW8 - MOST - May-05 - Toulouse
MOST - NGC2264
COROT/CW8 - MOST - May-05 - Toulouse
MOST - iota Leo
Target Type: F4IV solar type star
Goals: search for p-modes and granulation signals
Observing Dates: 16-Feb-2005 to 21-Mar-2005 - 33 days
Status: data reduction underway
While waiting ….. Serendipity struck again and with iota Leo we observed
a well studied double mode field RR Lyr star - AQ Leo and the results are
analyzed as we speak
COROT/CW8 - MOST - May-05 - Toulouse
MOST AQ Leo
COROT/CW8 - MOST - May-05 - Toulouse
MOST AQ Leo
COROT/CW8 - MOST - May-05 - Toulouse
MOST AQ Leo
COROT/CW8 - MOST - May-05 - Toulouse
MOST - tau Boo 2005
Target Type: F6IV solar type star with giant Jupiter
orbiting with a 3.3125 days period synchronized to the stars
rotation
Goals: follow up search for photometric signals from the planet
and for pulsations/granulation
Observing Dates: 21-Apr-2005 to 14-May-2005 - 23 days (7 cycles)
Status: observation were finished very recently but even preliminary
reduction reveals a very interesting nature of that star(-planet) system
COROT/CW8 - MOST - May-05 - Toulouse
MOST - tau Bootis
Groundbased photometry
 Strömgren b and y photometry from ground predicts that
star is nonvariable at orbital period
Baliunas et al. 1997 ApJ 474, L119
 amplitude limit: Δ(b+y)/2 < 0.4 mmag (400 ppm)
1 mmag
P
RV
COROT/CW8 - MOST - May-05 - Toulouse
= 3.3125 d
MOST - tau Bootis
2004
COROT/CW8 - MOST - May-05 - Toulouse
MOST - tau Bootis
2004
COROT/CW8 - MOST - May-05 - Toulouse
MOST - tau Bootis
2005
COROT/CW8 - MOST - May-05 - Toulouse
MOST - tau Bootis
2005
COROT/CW8 - MOST - May-05 - Toulouse
MOST - tau Bootis
2005
~ planet orbit/rotation period
COROT/CW8 - MOST - May-05 - Toulouse
MOST - tau Bootis
COROT/CW8 - MOST - May-05 - Toulouse
MOST - tau Bootis
 looks like an active young star?
 stellar modulation period = planet orbital period
 envelope of star tidally locked by planet?
 relatively large spot complex
 magnetospheric interaction?
 or travelling wave, induced by planet?
 phase of stellar light minimum leads
planetary conjunction by ~0.1 cycle
 weak secondary minimum (and first harmonic)
 evidence of tidal distortion of star?
 irregular variations from cycle to cycle
 Is tau Boo young or was it “rejuvenated” by planet?
COROT/CW8 - MOST - May-05 - Toulouse
MOST - tau Bootis
photometric detection of planetary
reflected light will be a challenge
 modulation and phasing
of stellar light curve offers
some hope, however
 How does the stellar
light variability affect
the radial velocity curve?
 rotational modulation could
show up in spectral line profiles
COROT/CW8 - MOST - May-05 - Toulouse
MOST - HD209458b
Transiting exoplanet system
 Spitzer detection of drop in thermal emission at 24μ
during eclipse
Deming et al. 2005 Nature 111, 111
COROT/CW8 - MOST - May-05 - Toulouse
MOST - HD209458b
 MOST trial run 2004 of Direct Imaging photometry
 searching for eclipse of planet to obtain albedo
 timing of known transit; search for other transits
14 days
Pplanet orbit = 50.06 × P MOST orbit
COROT/CW8 - MOST - May-05 - Toulouse
MOST - HD209458b
Looking for the optical eclipse
 phase diagram
 P = 3.52474895 ± 0.00000096 d RV ephemeris
1 mmag
phase of eclipse
Rowe, Matthews, Seager et al. 2005, in preparation
COROT/CW8 - MOST - May-05 - Toulouse
MOST - HD209458b

Spitzer: Fp /F = 0.0026 ± 0.0005 at λ = 24 μ

MOST: F p/F < 0.0008
*
*
at λ = 550 nm
 upper limit on depth of eclipse ~ 80 ppm
 upper limit on geometric albedo ~ 0.4
 Bond albedo expected to be lower
 Jupiter albedo in MOST bandpass ~ 0.5
 star to be reobserved for 1.5 months starting Aug 05
 should reduce detection limit to better than 0.2
COROT/CW8 - MOST - May-05 - Toulouse
MOST - eta Boo 2005
Target Type: G0IV Solar Type star
p-mode pulsations found from ground
Goals: repeat search for p-modes and granulation signal
Observing Dates: 31-Mar-2005 to 21-Apr-2005 - 21 days
Status: data reduction about be completed
But lets have look on what our results from the 2004 run are
COROT/CW8 - MOST - May-05 - Toulouse
MOST - eta Boo 2004
eta Boo
thin convective envelope
G0 IV, 1.7 M
post-ms, core H exhaustion
96% duty cycle over 27 days
More from Piet Reegen
in ~10 min
6 s integration 2 data points/min
COROT/CW8 - MOST - May-05 - Toulouse
MOST - eta Boo 2004
Echelle diagram
Models by D.B.Guenther
Saint Mary’s University
Canada
COROT/CW8 - MOST - May-05 - Toulouse
MOST - eta Boo 2004
MOST
Finds predominantly
Lower order l=0 modes
COROT/CW8 - MOST - May-05 - Toulouse
MOST - eta Boo 2004
Modes found
by MOST (circles)
no 1day alias shift was
needed for match not
a single one
COROT/CW8 - MOST - May-05 - Toulouse
MOST - eta Boo 2004
MOST and Kjeldsen
l=0 matching modes
COROT/CW8 - MOST - May-05 - Toulouse
MOST - eta Boo 2004
COROT/CW8 - MOST - May-05 - Toulouse
HR 1217
4-Nov-04 to
3-Dec-04 (29days)
Type: rapidly oscillation Ap star
best ever studied object of this
class obtained from ground based
multi-site ‘WET’ campaign data
Goals:
> verify the stable excitation of
previously known pulsation modes
> search for additional frequencies
> continuously monitor amplitude
variation over known 12.4 days
rotation period and magnetic cycle
time
Can MOST do better ??
COROT/CW8 - MOST - May-05 - Toulouse
HR 1217
4-Nov-04 to
3-Dec-04 (29days)
COROT/CW8 - MOST - May-05 - Toulouse
HR 1217
4-Nov-04 to
3-Dec-04 (29days)
 MOST campaign
 Nov-Dec 2004
666 hr over 29 days
duty cycle = 96%
30-sec integrations
MOST filter
 noise levels
 in original spectrum ~ 6
µmag (~ ppm)
 data not yet finally
reduced
 3 gaps due to cosmic ray
hits
50 ppm




12.5 d = rotation period
2004 MOST data
COROT/CW8 - MOST - May-05 - Toulouse
HR 1217
4-Nov-04 to
3-Dec-04 (29days)
 MOST finds…
 second magneticaly
perturbed (?) mode
 new p-modes matching
~34-µHz spacing
 tracking of amplitude &
phase modulation
 Implications
 most severe test yet of
magnetic perturbation
theories
COROT/CW8 - MOST - May-05 - Toulouse
MOST Observing Limits
COROT/CW8 - MOST - May-05 - Toulouse
MOST Observing Limits
COROT/CW8 - MOST - May-05 - Toulouse
MOST Observing Limits
observing condition - straylight
COROT/CW8 - MOST - May-05 - Toulouse
MOST Observing Limits
Power ok
~50% orbit
Outside CVZ
observing outside the CVZ
Power Limitations
>80% orbit
Power Limitations
>80% orbit
Observations Outside the CVZ for the first time
are planned for mid-June through July 2005
COROT/CW8 - MOST - May-05 - Toulouse
Power ok
~ 50% orbit
Outside CVZ