Download M. Meixner

The potential of JWST to Measure the MassLoss Return from Stars to Galaxies
M. Meixner (STScI), B. Sargent (STScI, RIT),
D. Riebel (JHU), S. Srinivasan (IAP),
& M. Otsuka (ASIAA)
Abstract
The JWST telescope will have the sensitivity and spectral
resolving power to analyze the mass-loss return from stars
to galaxies in the Local Volume of galaxies. For example,
color magnitude diagrams from photometric imaging with
NIRCam and MIRI can be used to identify dusty evolved
stars which can then be compared to precomputed models
such as GRAMS to derive dust mass loss returns.
Spectroscopy of sources with MIRI or NIRSpec can help
identify the dust species and correlate with type of star and
environment. Time monitoring of recent supernova
explosions can be performed to look for the signatures of
dust production. Measurements of elemental abundances
and dust content in planetary nebulae located in nearby
galaxies can support studies of dust production vs. metal
abundance in stars.
This Spitzer IRAC [8] vs IRAC [8] - MIPS [24] micron color-magnitude
diagram shows all the SAGE epoch 1 catalog point sources in grey
(Meixner et al. 2006). Over-plotted are SAGE sources with candidate
classifications as shown in the legend. The dashed line shows the
final expected sensitivity limit. The red line shows the anticipated
limit for MIRI/JWST using the same total integration time (~48
seconds) per pointing & band as Spitzer for LMC targets (its off the
bottom). The black solid lines show the brightness cutoff that would
be probed in such an integration for a galaxy at a distance of ~1 or 10
Mpc
A [8.0]-[24] CMD from SAGE observations. Black points are the
whole SAGE catalog. The colored points have spectra from Spitzer
IRS SAGE-Spec project (Kemper et al. 2010): red (new observations)
and blue (reprocessed archival observations). The thin line drawn at
the bottom of the plot labeled “S/N~10, 2hrs” indicates the [8.0]
magnitude at which MIRI could obtain a spectrum with a continuum
S/N of about 10 for a 2 hour integration. MIRI will therefore be able
to obtain high quality mid-infrared spectra of almost any evolved
star in the LMC.
Simulated MIRI CCD
SAGE-LMC CMD
Simulated MIRI CMD for M31
ASYMPTOTIC GIANT BRANCH AND RED SUPERGIANT STARS: The SAGE program for the LMC obtained Color-Magnitude Diagrams (CMDs) like the one at left (e.g., Srinivasan et al 2009). RSGs are red points, Orich AGBs are blue, C-rich AGBs are purple, and extreme AGBs best fit by C-rich (O-rich) models are green (black). By convolving preliminary JWST-MIRI filter transmission curves with best-fit models of AGB and RSG
stars, one obtains synthetic fluxes for MIRI bands. The fluxes of models that were best-fit to LMC SAGE observations of evolved stars were then scaled for evolved stars in M31 being at 780 pc (Peacock et al 2011) for the
CMD at center. The Color-Color Diagram (CCD) at right simulates how MIRI might distinguish between O-rich and C-rich evolved stars.
Conclusions:
JWST and MIRI in particular will be capable of directly
observing and quantifying the mass-loss return from stars to
galaxies by measuring the dust emission from AGB stars,
RSG stars, planetary nebulae and supernovae. Model grids
such as GRAMS will be important to make the analysis of
these data efficient; allowing for statistical analysis. We show
that JWST/MIRI will be able probe this mass loss return in
nearby galaxies, like the Andromeda Galaxy (M31), out to
the local volume (10 Mpc) via resolved stellar population
analysis. Thus, through application of JWST to this problem,
we can really understand the epoch of dust formation in the
Universe: when did dust first form in the Universe and how
has it affected the evolution of galaxies and our observations
of the Universe.
PLANETARY NEBULAE: O-rich planetary nebula SMP LMC 81
in the LMC and also scaled down if it were in N6822. For
comparison, the expected sensitivities of MIRI imaging and
spectroscopy modes are also plotted, for various S/N ratios and
integration times. MIRI will enable detailed studies of the very
final stages of stellar evolution for many nearby galaxies.
SUPERNOVAE: The predicted SEDs of H-rich SNe in d=20/40/80
Mpc, after 690 days explosion in d = 20, 40, and 80 Mpc. The SED of
SN2004et in NGC6946 at the same epoch (Fabbri et al. 2011) is used
as the template. When we select MIRI imaging mode, we would be
able to detect SNe within 80 Mpc with the MIRI filters <18 microns.
For example, in 2009, 33 H-rich SNe were discovered. Of them, 26
objects were in galaxies within 80 Mpc.
References:
Fabbri, J., Otsuka, M., Barlow, M.J. et al. 2011, MNRAS, 418, 1285
Kemper, C., Woods, P. et al. 2010, PASP, 122, 683
Meixner, M., Gordon, K., Indebetouw, R. et al. 2006, AJ, 132, 2268
Peacock, M., et al., 2011, arXiv:1105.3365
Riebel, D., et al., 2012, submitted
Sargent, B., et al., 2011, ApJ, 728, 93
Srinivasan, S., et al., 2009, AJ, 137, 4810
Srinivasan, S., et al., 2011, A&A, 532, A54
Ueta, T., & Meixner, M., 2003, ApJ, 586, 1338
Acknowledgements: Funding from NASA-ADAP, Herschel/HERITAGE, and NAG5 grants is acknowledged.