----- Attempting Submission 1 (Mon Jun 16 18:28:06 GMT 2008) ----- Assigned ID: 99 ----- Attempting Submission 1 (Wed Mar 05 22:55:00 GMT 2008) ----- Phase I Proposal 99 (UpperMass.apt) successfully submitted. What is the mass of the highest mass star? 100Mo? 150Mo? 200Mo? Or higher? Theory gives us little guidance as to what physics sets the upper mass limit, presuming one exists. Is it due to limitations in the highest masses that can coalesce? Or is it due to stability issues in such a behemoth? Observationally, the upper mass limit is poorly constrained at present, with the strongest evidence coming from the K-band luminosity function of the Arches cluster near the Galactic Center. Here we propose to investigate this question by determining the Initial Mass Function of NGC 3603, the nearest giant H II region. This cluster is known to contain a wealth of O3 and hydrogen-rich Wolf-Rayets, the most luminous and massive of stars. By constructing an accurate H-R diagram for the cluster, we will construct a present day mass function using newly computed high mass evolutionary tracks, and convert this to an initial mass function using the inferred ages. This will allow us to see whether or not there is a true deficit of high mass stars, evidence of an upper mass cutoff. At the same time we are likely to establish good masses for the highest mass stars ever determined. We have laid the groundwork for this project using the Magellan 6.5-m telescope and the excellent seeing found on Las Campanas, plus analysis of archival ACS/HRS frames, but we now need to obtain spectra of the stars unobservable from the ground. This can only be done with HST and a reburbished STIS.

We will be taking spectra of many stars in the NGC 3603 cluster, which fortuitously lies at a declination where it often in a CVZ. The field is relatively crowded' usually there are other equally bright stars within 0.5-1" of any given target. We will use the 0.2" slit, and so our observing stragety is to do a single ACQ at the start of each visit, using a bright, isolated star about 1' away from the targets. Doing individual ACQs would be not only costly in terms of observing time, but the crowing would compliate the situation. We will begin and end each visit with a short direct image in order to help look for eclipsing binaires. NGC 3603 is a rich, crowded cluster of O-type stars that fortunately lies smack in the middle of a CVZ, and we plan to fully utilize this. In general, our observing stragety is to do a single ACQ for each 4 or 5 orbit visit, and take spectra of multiple stars (with a single wavelength setting) throughout the visit. (We will occasionally redo the ACQ.) We begin and end each visit with a short, unfiltered direct image. HOT STARS 12 false 0.0 0.0 false false false false false SUPPORTED STAR MAIN SEQUENCE O B-V=1.03 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.01 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.03 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.03 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.02 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=0.98 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.04 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.00 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=0.96 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.06 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.02 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.01 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.06 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.01 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=0.99 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.09 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.01 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.04 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.04 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=0.99 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.06 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.06 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.00 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.06 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=0.97 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=0.99 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.05 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.02 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.08 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.02 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=0.99 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.01 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.04 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.14 J2000 00 00 0.0000 +00 00 0.00 J2000 STELLAR CLUSTER OB ASSOCIATION J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.02 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR MAIN SEQUENCE O B-V=1.02 J2000 00 00 0.0000 +00 00 0.00 J2000 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4194 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4706 STIS/CCD Spectroscopic No No G750M 6581 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Spectroscopic No No G430M 4451 STIS/CCD Imaging No No F28X50LP STIS/CCD Imaging No No 50CCD POS-TARG DITHER 0.5 LINE false false 5 90.0 STIS-ALONG-SLIT 1 false POS-TARG DITHER 0.567 LINE 0.567 false false 143.130102 4 26.6 STIS-CCD-BOX 2 false POS-TARG DITHER 0.5 LINE false false 3 90.0 STIS-ALONG-SLIT 3 false The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. /Users/massey/proposals/Cycle17/OP-cache/UpperMass-v01.xml 1213640064608 (Tic-Visit :proposal-id 11626 :visit-id "01" :proposal-version -1 :trans-version "20080609" :date "16-Jun-2008 11:14:22.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 1325408 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11626 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :cvz T :proposal-id 11626 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 27932 :al-overhead-at-end 0 :internal-dur-at-end 441 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 0 :low-sky "N" :pcs-visibility 0 :pcs-gap 0 ) true 5 0 The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. /Users/massey/proposals/Cycle17/OP-cache/UpperMass-v02.xml 1213640395915 (Tic-Visit :proposal-id 11626 :visit-id "02" :proposal-version -1 :trans-version "20080609" :date "16-Jun-2008 11:19:55.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 1399024 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11626 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :cvz T :proposal-id 11626 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 28003 :al-overhead-at-end 0 :internal-dur-at-end 401 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 0 :low-sky "N" :pcs-visibility 0 :pcs-gap 0 ) true 5 0 The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. /Users/massey/proposals/Cycle17/OP-cache/UpperMass-v03.xml 1213640074697 (Tic-Visit :proposal-id 11626 :visit-id "03" :proposal-version -1 :trans-version "20080609" :date "16-Jun-2008 11:14:31.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 1123040 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11626 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :cvz T :proposal-id 11626 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 21942 :al-overhead-at-end 0 :internal-dur-at-end 401 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 0 :low-sky "N" :pcs-visibility 0 :pcs-gap 0 ) true 4 0 The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. /Users/massey/proposals/Cycle17/OP-cache/UpperMass-v04.xml 1213640457982 (Tic-Visit :proposal-id 11626 :visit-id "04" :proposal-version -1 :trans-version "20080609" :date "16-Jun-2008 11:20:54.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 2098336 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11626 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :cvz T :proposal-id 11626 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 27961 :al-overhead-at-end 0 :internal-dur-at-end 421 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 0 :low-sky "N" :pcs-visibility 0 :pcs-gap 0 ) true 5 0 The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. /Users/massey/proposals/Cycle17/OP-cache/UpperMass-v05.xml 1213640122595 (Tic-Visit :proposal-id 11626 :visit-id "05" :proposal-version -1 :trans-version "20080609" :date "16-Jun-2008 11:15:17.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 1951120 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11626 :visit-id "05" :obset-id "05" :pcs-mode "FGS" ) (Tic-Orbit :cvz T :proposal-id 11626 :visit-id "05" :orbit-number 1 :pcs-time 333 :si-vis-utilization 22253 :al-overhead-at-end 0 :internal-dur-at-end 401 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 0 :low-sky "N" :pcs-visibility 0 :pcs-gap 0 ) true 4 0 The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. /Users/massey/proposals/Cycle17/OP-cache/UpperMass-v06.xml 1213640177859 (Tic-Visit :proposal-id 11626 :visit-id "06" :proposal-version -1 :trans-version "20080609" :date "16-Jun-2008 11:16:13.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 2724128 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11626 :visit-id "06" :obset-id "06" :pcs-mode "FGS" ) (Tic-Orbit :cvz T :proposal-id 11626 :visit-id "06" :orbit-number 1 :pcs-time 333 :si-vis-utilization 27991 :al-overhead-at-end 0 :internal-dur-at-end 421 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 0 :low-sky "N" :pcs-visibility 0 :pcs-gap 0 ) true 5 0