1 / 17

CSO and OVRO programs I. Evolution of Ices toward Low Mass Protostars

CSO and OVRO programs I. Evolution of Ices toward Low Mass Protostars. Main selection criterion based on previous detection of ice bands. SIRTF sources included as much as possible, but not exclusively .

serge
Download Presentation

CSO and OVRO programs I. Evolution of Ices toward Low Mass Protostars

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • Main selection criterion based on previous detection of ice bands. SIRTF sources included as much as possible, but not exclusively. • Important first order question: where are the ices? In circumstellar envelope or disk? Any processing? • Lines of sight complex: treat on source-to-source basis. Fraction IRS source list can be analyzed in detail.

  2. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • CSO: • 3*3 arcmin maps in HCO+ 3-2 and C18O 2-1 (or 13CO) in 32” beam for general environment and cloud structure. • C17O 2-1 and 3-2 on central position for T estimate. • CO 6-5 for presence warm gas and outflow. • Runs in Oct 2001 and June 2002. Decent weather, but hard to reduce because of technical difficulties (pointing problem, random line shifts).

  3. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • OVRO: • HCO+ 1-0, HCN 1-0, C18O 1-0, 13CO 1-0, 12CO 1-0 • corresponding 3 mm continuum • initially in low resolution L+E configurations (4-7” beam) for assessment smaller scale structure and filtering out foreground. • intention for high (H) resolution follow up on interesting sources.

  4. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • Elias 29 (Oph) [ISO] published • WL 22 ( Oph) [ISO] • Elias 32 ( Oph) [SIRTF] • Elias 33 ( Oph) [SIRTF] • WL 6 ( Oph) [SIRTF] • Elias 18 (Taurus) [ISO] EDGE-ON • CRBR 2422 ( Oph) [SIRTF] EDGE-ON • [L1489 IRS (Taurus)] EDGE-ON published • [RNO 91] EDGE-ON

  5. Where are the Ices? Elias 29  Oph • Lines of sight toward low mass protostars are often highly complex! • Interpretation of ice observations must be supported by mm-wave gas phase observations Boogert, Hogerheijde, Ceccarelli, et al., ApJ 570,708 (2002)

  6. Where are the Ices? • Line of sight Elias 29 is complex! • Face on disk located behind large column (AV=20) of cool (T< 40 K) foreground material which may well harbor the unprocessed ices. (Boogert, Hogerheijde, Ceccarelli, et al., ApJ 570,708, 2002)

  7. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • CRBR2422 (r Oph) • OVRO L+E (7” beam) • 3 mm continuum (color): <3 mJy (3s). Less than expected from 1.3 mm flux. • 13CO 1-0 (contour) 5.6 km/s

  8. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • CRBR2422 (r Oph) • OVRO L+E (7” beam) • 3 mm continuum (color): <3 mJy (3s). Less than expected from 1.3 mm flux. • 13CO 1-0 (contour) 5.2 km/s

  9. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • CRBR2422 (r Oph) • OVRO L+E (7” beam) • 3 mm continuum (color): <3 mJy (3s). Less than expected from 1.3 mm flux. • 13CO 1-0 (contour) 4.9 km/s

  10. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • Elias 18 (Taurus) • OVRO L+E (4” beam) • 3 mm continuum (contour) • 12CO 1-0 (color) 5.1 km/s

  11. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • Elias 18 (Taurus) • OVRO L+E (4” beam) • 3 mm continuum (contour) • 12CO 1-0 (color) 6.8 km/s

  12. CSO and OVRO programsI. Evolution of Ices toward Low Mass Protostars • Elias 18 (Taurus) • OVRO L+E (4” beam) • 3 mm continuum (contour) • 12CO 1-0 (color) 7.4 km/s • rotating disk? • no detection HCO+, HCN, CO isotopes

  13. CSO and OVRO programsII. 350 mm Observations of SIRTF/IRS YSOs • CSO/SHARC II: ~300 pixels at 350 mm. Sensitivity: 1s=27 mJy in 1 hour (incl. overhead). Corresponds to 1 mJy at 1.3 mm with spectral index of 2.5. • SHARC II observations will provide significant information within 1 hour even for weakest sources (many YSOs have 1.3 mm upper limit of 10-20 mJy). • Internal Caltech CSO proposal submitted Dec 2002 for 4 (half) nights likely in April. >20 YSOs in r Oph can be done. • Submm weather crucial: Mauna Kea weather improving w.r.t. recent years (El Nino effect?). Also: 2D array SHARC II cancels sky better. • 350 mm provides important information on dust mass and dust color temperature. Important addition to SIRTF/IRS spectra.

  14. ISO/SWS+LWS 2-200 mm spectrum Elias 29 (r Oph) with flared face-on disk model (Boogert et al. 2002, ApJ 570, 708).

  15. CSO and OVRO programsIII. Outflows in  Oph • PI: Hector Arce (Caltech/OVRO). • CSO proposal submitted Nov 2002 • Flux limited survey (F[1.3 mm] > 25 mJy) of outflows of YSOs in  Oph cloud in CO 3-2 line to do outflow statistics. • 52 YSOs selected, half of which are in c2d/IRS program. Sample includes Class I and Class II YSOs to study age effects. • Follow up on most interesting outflows at different evolutionary stages in CO 6-5 (CSO) and at high resolution (OVRO). • Link to evolutionary or inclination effects derived from IRS SEDs

  16. c2d/IRS Source Parameters Online http://www.astro.caltech.edu/~acab/SIRTF/select_sirtf.htmllogin: irspasswd: legacy • easy access to most up to date IRS source list all over the world • handy when preparing complementary observations or quick access needed during observing runs • easier to use than excel spreadsheet because database consists of 40+ columns for 200+ sources • select a range of parameters, e.g. M band magnitude between 5 and 8 is indicated as 5:8 • same as target list submitted to SSC • www links to SIMBAD and (limited) ADS

  17. c2d/IRS Source Parameters Online http://www.astro.caltech.edu/~acab/SIRTF/select_sirtf.htmllogin: irspasswd: legacy • now easy to update: • get master excel file ftp://ftp.astro.caltech.edu/users/acab/c2d_irs_db.xls • edit as needed. It is allowed to add new columns and rows • just do not use TABS (reserved for column separation) • use '##' for indicating a www link • send me the modified excel file • other possibilities: • add links to DSS and 2MASS images • add links to reduced SIRTF data

More Related