J/ApJ/869/L41 DSHARP I. Sample, ALMA obs. log and overview (Andrews+, 2018)
The Disk Substructures at High Angular Resolution Project (DSHARP).
I. Motivation, sample, calibration, and overview.
Andrews S.M., Huang J., Perez L.M., Isella A., Dullemond C.P.,
Kurtovic N.T., Guzman V.V., Carpenter J.M., Wilner D.J., Zhang S., Zhu Z.,
Birnstiel T., Bai X.-N., Benisty M., Hughes A.M., Oberg K.I., Ricci L.
<Astrophys. J., 869, L41 (2018)>
=2018ApJ...869L..41A 2018ApJ...869L..41A
ADC_Keywords: Millimetric/submm sources; Stars, masses; Stars, ages;
YSOs; Stars, distances; Surveys
Keywords: circumstellar matter; planets and satellites: formation;
protoplanetary disks
Abstract:
We introduce the Disk Substructures at High Angular Resolution Project
(DSHARP), one of the initial large programs conducted with the Atacama
Large Millimeter/submillimeter Array (ALMA). The primary goal of
DSHARP is to find and characterize substructures in the spatial
distributions of solid particles for a sample of 20 nearby
protoplanetary disks, using very high resolution (∼0.035", or 5au,
Full width half maximum (FWHM)) observations of their 240GHz (1.25mm)
continuum emission. These data provide a first homogeneous look at the
small-scale features in disks that are directly relevant to the planet
formation process, quantifying their prevalence, morphologies, spatial
scales, spacings, symmetry, and amplitudes, for targets with a variety
of disk and stellar host properties. We find that these substructures
are ubiquitous in this sample of large, bright disks. They are most
frequently manifested as concentric, narrow emission rings and
depleted gaps, although large-scale spiral patterns and small
arc-shaped azimuthal asymmetries are also present in some cases. These
substructures are found at a wide range of disk radii (from a few
astronomical units to more than 100au), are usually compact (≤10au),
and show a wide range of amplitudes (brightness contrasts). Here we
discuss the motivation for the project, describe the survey design and
the sample properties, detail the observations and data calibration,
highlight some basic results, and provide a general overview of the
key conclusions that are presented in more detail in a series of
accompanying articles.
Description:
The Disk Substructures at High Angular Resolution Project (DSHARP)
ALMA observations were conducted in 2017 May-November as part of
program 2016.1.00484.L. All measurements used the Band 6 receivers and
correlated data from four spectral windows (SPWs) in the dual
polarization mode. The continuum was sampled in three SPWs, centered
at 232.6, 245.0, and 246.9GHz, each with 128 channels spanning
1.875GHz (31.25MHz per channel). The remaining SPW was centered at the
12CO J=2-1 rest frequency (230.538GHz) and covered a bandwidth of
938MHz in 3840 channels (488kHz channel spacing, 0.64km/s velocity
resolution).
The plan was to observe each target briefly in the C40-5 (hereafter
"compact") configuration, and also for ∼1hr in the C40-8 or C40-9
(hereafter "extended") configurations. The compact observations are
necessary to recover emission on the larger angular scales that are
not sampled in the extended configurations. The actual observing log
is provided in Table 2.
We relied on archival ALMA observations of five targets (IMLup,
HD142666, Elias24, Elias27, and HD163296) instead of obtaining new
compact data, and folded in archival data for three other targets
(HD143006, AS 205,and AS209). Information about these data sets are
compiled in Table 3.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 123 20 The Disk Substructures at High Angular Resolution
Project (DSHARP) sample: host star properties
table2.dat 105 72 DSHARP observing log (ALMA Program 2016.1.00484.L)
table3.dat 104 24 Archival ALMA data sets used by DSHARP
fits/* . 42 Individual FITS files for the fiducial images
in 12CO J=2-1 and 240GHz (1.25mm) continuum
--------------------------------------------------------------------------------
See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
II/297 : AKARI/IRC mid-IR all-sky Survey (ISAS/JAXA, 2010)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/A+A/216/44 : Walraven photometry in Sco-Cen association (De Geus+, 1989)
J/A+A/379/564 : V-type & PMS stars UBVRI photo-polarimetry (Oudmaijer+ 2001)
J/AJ/130/1733 : Optical spectroscopy of ρ Oph stars (Wilking+, 2005)
J/A+A/447/609 : 1.2mm continuum observations in rho Oph cloud (Stanke+, 2006)
J/A+A/452/245 : Near-IR photometry of PMS stars in rho Oph (Natta+, 2006)
J/A+A/461/183 : Variability of classical T Tauri (Grankin+, 2007)
J/ApJ/671/1800 : SCUBA observations of ρ Oph cloud (Andrews+, 2007)
J/ApJS/177/551 : Spitzer c2d survey of Lupus dark clouds (Merin+, 2008)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/ApJ/734/98 : DISCS. II. Southern sky disk data (Oberg+, 2011)
J/ApJ/751/115 : Millimeter emission from Taurus binary systems (Harris+,2012)
J/ApJ/758/31 : IR photometry for members of Upper Sco (Luhman+, 2012)
J/ApJ/769/21 : Accretion luminosities young stars Pfβ (Salyk+, 2013)
J/ApJ/771/129 : Submillimetric Class II sources of Taurus (Andrews+, 2013)
J/ApJ/773/168 : Submm fluxes of very low-mass stars and BDs (Mohanty+, 2013)
J/A+A/578/L6 : Polarized images of MWC758 (Benisty+, 2015)
J/MNRAS/453/976 : Herbig Ae/Be X-shooter observations (Fairlamb+, 2015)
J/ApJ/820/83 : ALMA galaxy properties COSMOS survey field (Scoville+,2016)
J/ApJ/827/142 : ALMA observations of GKM stars in Upper Sco (Barenfeld+,2016)
J/ApJ/828/46 : ALMA survey of Lupus protoplanetary disks. I. (Ansdell+,2016)
J/A+A/600/A20 : Lupus YSOs X-shooter spectroscopy (Alcala+, 2017)
J/ApJ/847/31 : Protoplanetary disk data in Cha I and Lupus (Mulders+, 2017)
J/ApJ/845/44 : 340GHz SMA obs. nearby protoplanetary disks (Tripathi+,2017)
J/ApJ/849/63 : FIR-mm data of YSOs in star-forming regions (Ribas+, 2017)
J/A+A/610/A24 : AS 209 ALMA image (Fedele+, 2018)
J/AJ/156/76 : New young stars and brown dwarfs in Upper Sco (Luhman+, 2018)
J/ApJ/859/21 : ALMA survey Lupus protoplanetary disks. II. (Ansdell+, 2018)
J/ApJ/860/124 : ALMA continuum emission obs. of MWC 758 disk (Dong+, 2018)
http://almascience.org/alma-data/lp/DSHARP/ : Disk Substructures at High
Angular Resolution Project (DSHARP) home page
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name Target name
10 A1 --- f_Name Flag on name (1)
12- 20 A9 --- Region Associated star-forming region (2)
22- 38 A17 --- 2MASS 2MASS name (JHHMMSSss+DDMMSSs)
40- 42 I3 pc Dist [101/165] Distance (computed from the
Gaia DR2 parallaxes)
44- 45 I2 pc e_Dist [2/10] Minimal error on distance
47- 48 I2 pc E_Dist [19]? Maximal error on distance, only if
different from minimal error
50- 53 A4 --- SpT Spectral type from the literature
55- 58 F4.2 [K] logTeff [3.5/4] Effective temperatures from the
literature
60- 63 F4.2 [K] e_logTeff [0.01/0.03] Error on logTeff
65- 69 F5.2 [Lsun] logL [-0.7/1.3] Stellar luminosities from the
literature, scaled according to the
appropriate distance
71- 74 F4.2 [Lsun] e_logL [0.1/0.3] Error on logL
76- 79 F4.2 [Msun] logM [0/0.8] Stellar masses
81- 84 F4.2 [Msun] e_logM [0.01/0.19] Minimal error on logM
86- 89 F4.2 [Msun] E_logM [0.03/0.2] Maximal error on logM
91 A1 --- l_logAge ? Limite flag on logAge
93- 95 A3 [yr] logAge Stellar age (logt*)
97- 99 F3.1 [yr] e_logAge [0.3/0.8]? Minimal error on age
101-103 F3.1 [yr] E_logAge [0.1/0.6]? Maximal error on age, only if
different from minimal error
105 A1 --- l_logdM/dt ? Limit flag on logdM/dt
107-110 A4 [Msun/yr] logdM/dt Accretion rates, inferred from (properly
scaled) accretion luminosities (3)
112-114 F3.1 [Msun/yr] e_logdM/dt [0.3/0.5]? Error on logdM/dt
116-123 A8 --- Ref References (4)
--------------------------------------------------------------------------------
Note (1): Flags as follow:
a = HTLup (Sz68) and AS205 (V866Sco) are triple systems.
See Kurtovic+ (2018ApJ...869L..44K 2018ApJ...869L..44K) for more details.
b = The MY Lup disk is inclined and flared enough that it likely
extincts the host: the L* and t* estimates may be too faint and old,
respectively.
Note (2): The Lup subcloud regions are as designated by
Cambresy (1999A&A...345..965C 1999A&A...345..965C). Upper Sco memberships were made
following Luhman+ (2018, J/AJ/156/76). AS209 and WaOph6 are located
well northeast of the main Oph region in the OphN3a complex. They are
most closely associated with the L163 and L162 dark clouds, respectively.
Note (3): All quoted measurements correspond to the peak of the marginalized
posterior distributions. Uncertainties reflect the 68.3% confidence
interval; limits are taken at the 95.5% confidence level.
Note (4): References as follow:
1 = Alcala+ (2017, J/A+A/600/A20)
2 = Fairlamb+ (2015, J/MNRAS/453/976)
3 = Luhman & Mamajek (2012, J/ApJ/758/31)
4 = Barenfeld+ (2016, J/ApJ/827/142)
5 = Rigliaco+ (2015ApJ...801...31R 2015ApJ...801...31R)
6 = Salyk+ (2013, J/ApJ/769/21)
7 = Luhman & Rieke (1999ApJ...525..440L 1999ApJ...525..440L)
8 = Andrews+ (2010ApJ...723.1241A 2010ApJ...723.1241A)
9 = Natta+ (2006, J/A+A/452/245)
10 = Andrews+ (2009ApJ...700.1502A 2009ApJ...700.1502A)
11 = Wilking+ (2005, J/AJ/130/1733)
12 = Muzerolle+ (1998AJ....116.2965M 1998AJ....116.2965M)
13 = Bouvier & Appenzeller (1992A&AS...92..481B 1992A&AS...92..481B)
14 = Eisner+ (2005ApJ...623..952E 2005ApJ...623..952E)
15 = Herbig & Bell (1988cels.book.....H 1988cels.book.....H)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name Target Name
10- 19 A10 "Y:M:D" obs.date UTC date at the start of the observations
21- 25 A5 "h:m" obs.time UTC time at the start of the observations
27- 33 A7 --- Config ALMA configuration
35- 37 I3 m Bmin [15/139] Minimum baseline length
39- 42 F4.1 km Bmax [1.1/16.2] Maximum baseline length
44- 45 I2 --- Nant [39/51] Number of antennas available
47- 48 I2 deg Emin [27/79] Minimum target elevation range
(ε)
50- 51 I2 deg Emax [39/87] Maximum target elevation range
(ε)
53- 56 F4.2 mm PWVmin [0.3/1.5] Minimum range of precipitable
water vapor levels
58- 61 F4.2 mm PWVmax [0.4/1.9] Maximum range of precipitable
water vapor levels
63-105 A43 --- Cal Calibrators (1)
--------------------------------------------------------------------------------
Note (1): From left to right, the quasars observed for calibrating the bandpass,
amplitude scale, phase variations, and checking the phase transfer.
Additional archival observations used in our analysis are compiled in
Table 3.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Name Target Name
10- 19 A10 "Y:M:D" obs.date UTC date at the start of the observations
21- 25 A5 "h:m" obs.time UTC time at the start of the observations
27- 33 A7 --- Config ALMA configuration
35- 36 I2 m Bmin [15/43] Minimum baseline length
38- 41 I4 m Bmax [349/3144] Maximum baseline length
43- 44 I2 --- Nant [15/44] Number of antennas available
46- 86 A41 --- Cal ? Calibrators (1)
88-101 A14 --- Prog ALMA program ID
103-104 I2 --- Ref ? Original references for these data sets
(2)
--------------------------------------------------------------------------------
Note (1): From left to right, the quasars observed for calibrating the bandpass,
amplitude scale, phase variations, and checking the phase transfer.
No entry indicates no calibrator was observed for checking the phase
transfer.
Note (2): References as follow :
1 = Oberg+ (2015ApJ...810..112O 2015ApJ...810..112O)
2 = Cleeves+ (2017ApJ...842L...3C 2017ApJ...842L...3C)
3 = Pinte+ (2018A&A...609A..47P 2018A&A...609A..47P)
4 = Salyk+ (2014ApJ...792...68S 2014ApJ...792...68S)
5 = Dipierro+ (2018MNRAS.475.5296D 2018MNRAS.475.5296D)
6 = Perez+ (2016Sci...353.1519P 2016Sci...353.1519P)
7 = Huang+ (2016ApJ...823L..18H 2016ApJ...823L..18H)
8 = Fedele+ (2018, J/A+A/610/A24)
9 = Flaherty+ (2015ApJ...813...99F 2015ApJ...813...99F)
10 = Isella+ (2016PhRvL.117y1101I 2016PhRvL.117y1101I)
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History:
From electronic version of the journal for the tables.
FITS files downloaded at:
http://almascience.eso.org/almadata/lp/DSHARP/images/
References:
Huang et al. Paper II 2018ApJ...869L..42H 2018ApJ...869L..42H Cat. J/ApJ/869/L42
Huang et al. Paper III 2018ApJ...869L..43H 2018ApJ...869L..43H
Kurtovic et al. Paper IV 2018ApJ...869L..44K 2018ApJ...869L..44K
Birnstiel et al. Paper V 2018ApJ...869L..45B 2018ApJ...869L..45B
Dullemond et al. Paper VI 2018ApJ...869L..46D 2018ApJ...869L..46D
Zhang et al. Paper VII 2018ApJ...869L..47Z 2018ApJ...869L..47Z
Isella et al. Paper IX 2018ApJ...869L..49I 2018ApJ...869L..49I
Perez et al. Paper X 2018ApJ...869L..50P 2018ApJ...869L..50P
(End) Prepared by [AAS], Coralie Fix [CDS] 13-Jan-2020