Submission failed communicating with the submission server: java.rmi.ConnectException: Connection refused to host: 130.167.201.116; nested exception is: java.net.ConnectException: Connection refused Submission failed communicating with the submission server: java.rmi.ConnectException: Connection refused to host: 130.167.201.116; nested exception is: java.net.ConnectException: Connection refused Submission failed communicating with the submission server: java.rmi.ConnectException: Connection refused to host: 130.167.201.116; nested exception is: java.net.ConnectException: Connection refused Submission failed communicating with the submission server: java.rmi.ConnectException: Connection refused to host: 130.167.201.116; nested exception is: java.net.ConnectException: Connection refused Submission failed communicating with the submission server: java.rmi.ConnectException: Connection refused to host: 130.167.201.116; nested exception is: java.net.ConnectException: Connection refused Assigned ID: 220 ----- Attempting Submission 1 (Thu Feb 23 21:35:39 GMT 2012) ----- HST Phase I Proposal 220 (eMSTOprop.apt) successfully submitted. ----- Attempting Submission 2 (Fri Feb 24 13:59:00 GMT 2012) ----- HST Phase I Proposal 220 (eMSTOprop.apt) successfully submitted. ----- Attempting Submission 1 (Fri Jun 29 16:08:20 GMT 2012) ----- What Causes Extended Main Sequence Turn-offs in Intermediate-Age Star Clusters? Recently, deep images from the ACS camera aboard HST provided conclusive evidence that several massive intermediate-age star clusters in the Magellanic Clouds present extended main-sequence turn-off regions (eMSTOs), and in some cases also dual red clumps. These observations challenge the notion that star clusters are simple stellar populations, and pose serious questions regarding the mechanisms responsible for star cluster formation. We propose to collect HST imaging that should lead to an understanding of the nature of the eMSTO phenomenon. We will perform deep WFC3 imaging in F438W and F814W for 3 Magellanic Cloud star clusters whose ages and dynamical properties (mass, radius) will allow a critical study of the physical conditions that cause the eMSTO phenomenon. The data will allow us to derive detailed star formation histories via CMD reconstruction methods. The underlying field population will be characterized by means of ACS images of nearby areas obtained in parallel. Without high-quality HST imaging data for these three pivotal clusters, the discussion regarding the onset of multiple stellar populations in star clusters may persist for years. The target star clusters are observed with WFC3 using the F438W and F814W filters. Since the shape and position of the red giant branch (RGB) in the color-magnitude diagram (CMD) is used to determine metallicities, we include exposures in each filter that do not saturate the bright giants. On the other hand, we need color uncertainties less than 0.05 mag down to well beyond the estimated magnitude of the main sequence turnoff to achieve an accurate age determination and to enable a robust identification of multiple turnoff structures if the target cluster in question has multiple stellar populations. Hence, at least one short exposure is used in each filter to avoid saturation of the giants and red clump stars, while at least two longer exposures are used to achieve deep photometry. At least two dither positions are used for each target star cluster to allow a robust elimination of hot pixels and cosmic ray hits during the analysis. ACS is used in parallel to the primary WFC3 exposures, using the filters F435W and F814W. This will allow a robust determination of the field population contribution to the star cluster pointings. RESOLVED STELLAR POPULATIONS 12 false 0.0 0.0 false false false false SUPPORTED STELLAR CLUSTER GLOBULAR CLUSTER This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 STELLAR CLUSTER GLOBULAR CLUSTER This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 STELLAR CLUSTER GLOBULAR CLUSTER This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 WFC3/UVIS Imaging No No F438W WFC3/UVIS Imaging No No F814W ACS/WFC Imaging No No F435W ACS/WFC Imaging No No F814W WFC3/UVIS Imaging No No F438W WFC3/UVIS Imaging No No F814W ACS/WFC Imaging No No F435W ACS/WFC Imaging No No F814W WFC3/UVIS Imaging No No F438W WFC3/UVIS Imaging No No F814W ACS/WFC Imaging No No F435W ACS/WFC Imaging No No F814W The scheduling data was generated by CASM 20.2. CASM was run in Phase II mode. 3950 /Users/goudfroo/propo/HST/Cycle20/12908/OP-cache/eMSTOprop-v01.xml Applies to NGC 2209. Visit orientation constraints to avoid bright stars close to the edges of the ACS FOV. (Tic-Visit :proposal-id 12908 :visit-id "01" :proposal-version -1 :trans-version "20120604" :date "29-Jun-2012 12:00:25.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 2580640 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12908 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12908 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3302 :al-overhead-at-end 112 :internal-dur-at-end 1015 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3635 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 20.2. CASM was run in Phase II mode. 3950 /Users/goudfroo/propo/HST/Cycle20/12908/OP-cache/eMSTOprop-v02.xml Applies to NGC 2249. Visit orientation constraints to avoid bright stars close to the edges of the ACS FOV. (Tic-Visit :proposal-id 12908 :visit-id "02" :proposal-version -1 :trans-version "20120604" :date "29-Jun-2012 12:00:29.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 2580640 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12908 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12908 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3244 :al-overhead-at-end 0 :internal-dur-at-end 1015 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3582 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 20.2. CASM was run in Phase II mode. 3950 /Users/goudfroo/propo/HST/Cycle20/12908/OP-cache/eMSTOprop-v03.xml Applies to NGC 152. Visit orientation constraints to avoid bright stars close to the edges of the ACS FOV. (Tic-Visit :proposal-id 12908 :visit-id "03" :proposal-version -1 :trans-version "20120604" :date "29-Jun-2012 12:00:10.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 2291888 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12908 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12908 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2740 :al-overhead-at-end 50 :internal-dur-at-end 1015 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3073 :pcs-gap 0 ) true 1 0