Massive Star Astrophysics with MCSF Dominik J. Bomans

Massive Star Astrophysics
with MCSF
Dominik J. Bomans,
Alexander Becker, & Kerstin Weis
Astronomical Institute of the Ruhr-University Bochum
and
Research Department “Plasmas with complex interactions”
of the Ruhr-University Bochum
Colosimo
Unfortunately for funding , it is not
Stellar Astrophysics with MSFC
(the Manchester City Football Club)
MC S F
but the
Magellanic Clouds Massive Stars and Feedback survey
Power of “complete” datasets
But how complete are we?
For example:
how complete is our census
of Wolf-Rayet star in the
Magellanic Clouds?
Hainich et al. 2014
Why another MC survey ?
DPOSS etc.: photographic, no narrow band
SHS (Parker et al. 2005): photographic, only H and SR
2MASS (Cutrie et al. 2012): only NIR, no narrow band
Spitzer (Gordon et al. 2011): MIR
MCPS (Zaritsky et al. 1999) : problems at brightest stars, no narrow band data
OGLE (Udalski et al. 2008): saturated at ~ -6, no narrow band data
(Massey et al. 2002) Not spatially complete, no narrow band
MCELS (Smith et al. 1998): narrow band, only 2 (non-standard) broad-band filters
→ niche for complete, multi band (broad and narrow) optical survey
What is MCSF ?
MCSF:
Magellanic Clouds massive Stars and their Feedback survey
u, B, V, R, I, H, [OIII], [SII] imaging of both LMC and SMC
Complete coverage spatially (LMC ~ 8̊ x 8̊
SMC ~4.5̊x 2.5̊)
and in brightness (currently down to MB ~ 0)
→ spatial resolution and depth comparable to HST data
of Local Group galaxies
RoBoTT @ Cerro Armazones
Robotic Bochum Telescope = RoBoTT
2x 150mm refractor on common mount
FOV each:: 2̊42' x 2̊42' on 4096^2 CCD
Pixelscale 2.37”/pix
Fields
LMC (B,V,R)
SMC (B,R,Hα)
LMC N11
MCSF data example (Hα):
The superbubble/starforming
complex N11
In the LMC
Data reduction
LMC: 9 fields, SMC: 2 fields of 4096^2 pixels
Even brightest LMC stars not saturated on short exposure frames
Many frames, of several integration times → similar to Multi-CCD Cameras
Uses THELI Pipeline (Erben et al. 2005), version 2012
→accuate astrometry, correction for distortions, excellent flat-fielding,
correction for residual pixel to pixel variations, and mosaicking
Drizzling to new pixel scale of 1”
Different dataproducts generated:
- deep
- shallow
- individual epochs
Automated photometry with modfied DoPhot (Alonso-Garcia et al. 2012)
- spatial variable PSF possible
- artificial star experiments for completeness and photometric error estimates
Hess Diagram LMC
1.9 106 stars
Hess Diagram SMC
0.5 106 stars
Emissionline Stars
red = SMC
blue = LMC
increasing fractition
of emission line stars
with mass
Oe / Be stars
red = SMC
blue = LMC
Higher Be content in SMC
Increase towards lower luminosity
SMC/LMC ratio roughly constant
In B star regime
Value of ratio
consistent with Iqbal & Keller 2013
But ow compared to
e.g. Martayan et al. 2010
O9.5V
B0V
Current MCSF catalog contains
~500 Be stars In the SMC
and
~670 Be stars in the LMC
CMD to HRD with astro-informatics
Clean CMD from foreground stars
Match database with UV (GALEX, SWIFT), NIR, MIR (Spitzer)
Estimate spectral class from SED with maschine learning techniques
(train algorithm with (many) stars of known classification)
→ 80000 stars with approximate “spectral” type
98% of training set recovered
Still residuals due to incomplete
photometry
and fragmentary training set
Resulting HRD of SMC
Overplotted:
Geneva tracks with rotation
(Georgy et al. 2013)
Search of WR stars
Again via astro-informaticts:
Create training set with spectral
Classification and use UV-IR
Multi-band photometry
MCSF CMDs of LMC (up) and SMC (right)
training sample with spectral classification
New early O and WR candidates
Probability distribution for all stars
to be part of each trained category
(e.g. LMC)
Candidates for new hot supergiants in the
LMC with stellar tracks (60 M⊙, 40 M⊙, 30
M⊙) with rotation (Meynet & Maeder. 2004)
Doing okay?
Compare with new WR stars from Massey et al. (2014)
Check currently limited
To B < 16 mag in LMC
and B < 17 mag in SMC
ID
Massey
MCSF
LMC143-1
WN3 + O8-9III
WR
LMC173-1
WN3 + O7.5V
Be
SMC159-2
O8f?p
B1/5III
LMC156-1
O6If
O4V((f))
LMC164-2
O8f?p
WN4.5
LMC173-2
O7.5Iaf
O9.7Ia
LMC174-4
O4Ifc
A1Iab
LMC174.5
B[e]+WN?
Be
Waiting for ESO about follow-up spectroscopy proprosal for 150 candidates.
Luminous Variables in the SMC
HD 5980
AzV 320
To do …
Improve foreground cleaning
add more UV photometry
upgrade NIR from 2MASS to VMC (Cioni et al. 2011)
update spectral classification database
Investigate binary evolution at highest mass bins
IMF and Lyman continuum flux analysis in superbubbles
Diffuse ionized gas and link to X-rays
...
…. and work on the archive ….
MCSF Archive
http://www.astro.rub.de/Astronomie/MCSF
Just started, currently some technical info, pretty pictures, and CMDs
It will contain full photometry, cross-match with NIR, MIR, and UV, and
images...
First subsets of the in photometry in fall.
... Alexander has to work on papers for his thesis, too....
If you need some data urgently, please contact us...
Image: Ch. Malin

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