IRAS16293Band9: Difference between revisions

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[[Category:ALMA]] [[Category:Calibration]] [[Category:Spectral line]]
[[Category:ALMA]] [[Category:Calibration]] [[Category:Spectral line]]


==Science target overview==
==Science Target Overview==


IRAS 16293-2422 (d=160 pc; Chini 1981) is a well studied nearby Class 0 proto-binary system (consists of source A and source B) located in L1689 (i.e., Ophiuchus star forming cloud). The projected separation between source A and B is ~5" (Mundy et al. 1992; Chandler et al. 2005; Figure 1 left panel). Sub-arcsecond VLA and SMA centimeter and  millimeter/submillimeter continuum images have spatially resolved source A as several components associated with protostars and jets (Chandler et al. 2005; Pech et al. 2010).
IRAS 16293-2422 (d=160 pc; Chini 1981) is a well studied nearby Class 0 proto-binary system (consists of sources A and B) located in L1689 (i.e., Ophiuchus star forming cloud). The projected separation between sources A and B is roughly 5" (Mundy et al. 1992; Chandler et al. 2005; Figure 1 left panel). Sub-arcsecond VLA and SMA centimeter and  millimeter/submillimeter continuum images have spatially resolved source A as several components associated with protostars and jets (Chandler et al. 2005; Pech et al. 2010).
IRAS 16293-2422 hosts a large-scale quadrupolar outflow (Walker et al. 1988; Mizuno et al. 1990; Castets et al. 2001; Hirano et al. 2001; Garay et al. 2002; Stark et al. 2004; Yeh et al. 2008). The outflow aligned in the east-west direction is currently active and likely originated from source A (Figure 1 right panel). The origin of the other large-scale outflow  aligned in the northeast-southwest direction is not clear.  
IRAS 16293-2422 hosts a large-scale quadrupolar outflow (Walker et al. 1988; Mizuno et al. 1990; Castets et al. 2001; Hirano et al. 2001; Garay et al. 2002; Stark et al. 2004; Yeh et al. 2008). The outflow aligned in the east-west direction is currently active and likely originated from source A (Figure 1 right panel). The origin of the other large-scale outflow  aligned in the northeast-southwest direction is not clear.  
Previous molecular line studies with the SMA have revealed detailed structure and kinematics in the circumbinary envelope for each component. These imply gas infall and outflow motions (Chandler et al. 2005; Takakuwa et al. 2007; Yeh et al. 2008).
Previous molecular line studies with the SMA have revealed detailed structure and kinematics in the circumbinary envelope for each component. These imply gas infall and outflow motions (Chandler et al. 2005; Takakuwa et al. 2007; Yeh et al. 2008).
In addition, IRAS 16293-2422 exhibits strong emission from a number of complex organic molecules and other species usually associated with hot cores in massive star-forming regions, especially towards source A (e.g., Blake et al. 1994; van Dishoeck et al. 1995; Bottinelli et al. 2004; Kuan et a. 2004; Schoier et al. 2004; Chandler et al. 2005; Huang et al. 2005; Bisschop et al. 2008; Jorgensen et al. 2011; Caux et al. 2011).  
In addition, IRAS 16293-2422 exhibits strong emission from a number of complex organic molecules and other species usually associated with hot cores in massive star-forming regions, especially towards source A (e.g., Blake et al. 1994; van Dishoeck et al. 1995; Bottinelli et al. 2004; Kuan et a. 2004; Schoier et al. 2004; Chandler et al. 2005; Huang et al. 2005; Bisschop et al. 2008; Jorgensen et al. 2011; Caux et al. 2011).  
Finally, source B shows narrow line width (Bisschop et al. 2008; Jorgensen et al. 2011) and no clear signature of outflow (Chandler et al. 2005). This suggests that the source may be at the very young evolutionary stage; likely even before the mass accretion/loss processes start.
Finally, source B shows a narrow line width (Bisschop et al. 2008; Jorgensen et al. 2011) and no clear signature of outflow (Chandler et al. 2005). This suggests that the source may be at the very young evolutionary stage; likely even before the mass accretion/loss processes start.


[[File:intro.jpg|200px|thumb|right|'''Fig. 1.''' Left: Sub-arcsecond continuum image obtained with SMA at 310 GHz by Chandler et al. (2005). Right: Integrated blueshifted and redshifted CO (2-1) image tracing molecular outflow originated from source A. The data were obtained with SMA by Yeh et al. (2008). The emission is integrated over the velocity channels from V_lsr=-7.2 to 3.3 km/s on the blueshifted side and from V_lsr=5.5 to 31.9 km/s on the redshifted side.]]
[[File:intro.jpg|200px|thumb|right|'''Fig. 1.''' Left: Sub-arcsecond continuum image obtained with SMA at 310 GHz by Chandler et al. (2005). Right: Integrated blueshifted and redshifted CO (2-1) image tracing molecular outflow originated from source A. The data were obtained with SMA by Yeh et al. (2008). The emission is integrated over the velocity channels from V_lsr=-7.2 to 3.3 km/s on the blueshifted side and from V_lsr=5.5 to 31.9 km/s on the redshifted side.]]


==ALMA data description==
==ALMA Data Overview==


ALMA Science Verification data at Band 9 (602-720 GHz) was taken for IRAS 16293-2422 on April 16 and 17, 2012. The observations have been performed with a seven pointing mosaic centered at RA=16h 32m 22.7s, Dec=-24d28’32.5’’ as shown in Figure 1. The complete 7 pointing for the mosaic are shown in Figures 2 and 3, overlapping them with relevant figures from the literature.  
ALMA Science Verification data at Band 9 (602-720 GHz) was taken for IRAS 16293-2422 on April 16 and 17, 2012. The observations have been performed with a seven pointing mosaic centered at RA=16h 32m 22.7s, Dec=-24d28’32.5’’ as shown in Figure 1. The complete 7 pointing mosaic can be seen in Figure 2, superposed on archival SMA data for better visualization.  


A scheduling block about 2.3 hours long was run four times for a total of about 9.2 hours of observing time. The integration time of each visibility pointing is 6.048 sec, and total on-source time of the target is between 16 and 20 min in each field. Three data sets were obtained at post-transit, while the other one was obtained at pre-transit. The name of the four ASDMs are as follows:
A scheduling block about 2.3 hours long was run four times for a total of about 9.2 hours of observing time. The integration time of each visibility is 6.048 sec, and the total on-source time of of each pointing is between 16 to 20 min. Three data sets were obtained post-transit, while the other one was obtained pre-transit. The name of the four ASDMs are as follows (with the median value
of zenithal precipitable water vapor given in parentheses):


*uid___A002_X3d4118_X39b
*uid___A002_X3d4118_X39b (0.31 mm)
*uid___A002_X3d55cb_X575
*uid___A002_X3d55cb_X575 (0.65 mm)
*uid___A002_X3d55cb_Xb50
*uid___A002_X3d55cb_Xb50 (0.43 mm)
*uid___A002_X3d55cb_X90c
*uid___A002_X3d55cb_X90c (0.41 mm)


Data were obtained with the Double Sideband (DSB) receivers. Four available basebands were used for obtaining data with Frequency Division Mode (FDM). The CO (6-5) line at a rest frequency of 691.473 GHz is located in spw=1 (the spw number after split). The other three spectral windows (spw=0, 2, and 3) do not contain strong spectral lines as CO (6-5) so that these spws were used for continuum imaging for this casa guide. However, please note that a number of weak molecular lines were also detected in these spectral windows, and further imaging analysis using these weak lines could be possible. Each spectral window is 1.875 GHz in width, and contains 3840 channels. The frequency resolution corresponds to 0.488 MHz (0.2 km/s). Because the ALMA correlator was configured to apply Hanning smoothing of the signal, the effective spectral resolution is about twice the channel width, and so the velocity resolution.
Data were obtained with the Double Sideband (DSB) Band 9 receivers. Four basebands were used for obtaining data with Frequency Division Mode (FDM). The baseband centers are located at approximately: 704.249, 691.299, 689.499, and 687.499 GHz. The CO (6-5) line at a rest frequency of 691.473 GHz is strongly detected (though extremely resolved out), along with numerous other weaker (but more compact) organic species throughout all four basebands. Each spectral window is 1.875 GHz in width, and contains 3840 channels. The channel separation is 0.488 MHz (0.2 km/s), but the spectral resolution is factor of 2 poorer (0.4 km/s) due to online Hanning smoothing. The image cubes were made with
0.4 km/s channels.  


The array was used in the corresponding Early Science Cycle 0 extended configuration. The expected angular resolution at the frequency of the CO (6-5) line is about 0.2 arcsec.
These data were obtained using the Cycle 0 Early Science extended configuration which resulted in an angular resolution of about 0.22"


[[File:FOVs.jpg|200px|thumb|right|'''Fig. 2.''' Pointings (crosses) and field of view (circles with 9”) for IRAS 16293-2422 Band 9 observations overlaid on SMA continuum image obtained at 310 GHz referred from Chandler et al. 2005.]]
[[File:FOVs-2.jpg|200px|thumb|right|'''Fig. 2.'''Pointings (crosses) and field of view (circles with 9”) for the ALMA band 9 SV observations toward IRAS 16293-2422 overlaid on SMA continuum image at 310 GHz obtained with the extended configuration (angular resolution of 0.97”x0.76”). The SMA data were retrieved from archive. The positions of source Aa, Ab, and B reported in Chandler et al. (2005) are denoted by the black dots.]]


[[File:FOVs-2.jpg|200px|thumb|right|'''Fig. 3.'''Pointings (crosses) and field of view (circles with 9”) for the ALMA band 9 SV observations toward IRAS 16293-2422 overlaid on SMA continuum image at 310 GHz obtained with the extended configuration (angular resolution of 0.97”x0.76”). The SMA data were retrieved from archive. The positions of source Aa, Ab, and B identified by Chandler et al. (2005) are denoted by the black dots.]]
'''Using the data for publication''': Please use the acknowledgement given at the bottom of the [https://almascience.nrao.edu/alma-data/science-verification Science Verification Data page].


==Download the data==
We thank the following people for suggesting IRAS16293 for ALMA Science Verification: Jes Jorgensen, Suzanne Bisschop, Ewine van Dishoeck, Tyler Bourke, Johan Lindberg, Michiel Hogerheijde, Bill Dent, Martin Zwaan, Al Wootten.
 
==Obtaining the Data==


To download all the data, follow one of the next links:
To download all the data, follow one of the next links:


[https://almascience.nrao.edu/almadata/sciver/IRAS16293B9 North America]
[https://almascience.nrao.edu/almadata/sciver/IRAS16293Band9/ North America]


[http://almascience.eso.org/almadata/sciver/AntennaeBand7 Europe]
[http://almascience.eso.org/almadata/sciver/IRAS16293B9 Europe]


[http://almascience.nao.ac.jp/almadata/sciver/AntennaeBand7 East Asia]
[http://almascience.nao.ac.jp/almadata/sciver/IRAS16293B9 East Asia]


The links provide you with the option to download the following gzipped tar files:
The links provide you with the option to download the following gzipped tar files:


'''IRAS16293_Band9_UnCalibratedMSandTablesForReduction''' - The file contains the raw data files in ALMA Science Data Model (ASDM) format already converted into CASA Measurement Sets (MS) using {{importasdm}} inside CASA. The tables that are needed to calibrate the data are also provided.
'''IRAS16293_Band9_UnCalibratedMS''' - The file contains the raw data files in ALMA Science Data Model (ASDM) format already converted into CASA Measurement Sets (MS) using {{importasdm_6.6.1}} inside CASA.  
 
'''IRAS16293_Band9_CalibratedMS_FIXED''' - The fully-calibrated u-v data, ready for imaging.
 
'''IRAS16293_Band9_ReferenceImages_FIXED''' - The final continuum and spectral line images.  


'''IRAS16293_Band9_CalibratedData''' - The fully-calibrated u-v data, ready for imaging.  
<pre style="background-color: #ffa07a;">
WARNING: On June 15, 2012 the calibration guide and the final data products (calibrated science
data: IRAS16293_Band9_CalibratedMS_FIXED.tgz and reference images: IRAS16293_Band9_ReferenceImages_FIXED.tgz))
were changed to correct for a 1.2" position error in the phase calibrator (1625-254). Without
correction, the science images will suffer from a similar offset.  
</pre>


'''IRAS16293_Band9_ReferenceImages''' - The final continuum and spectral line images.  
You can work with these data products at any of the three stages: the UnCalibratedMS, the Calibrated MS (ready for imaging, or the ReferenceImages. Warning: the UnCalibrated data is large.


Depending on how you want to proceed to work with the IRAS16293 data, download the file that corresponds.
'''Caveat:''' Before using the ReferenceImages for scientific purposes, please note that only a few of the very strongest lines have been excluded from the continuum subtraction or continuum imaging - you may wish to do a  more careful job if your science application is strongly dependent on the flux density or morphology of source B, in particular which shows both strong absorption and emission at the 0.2" resolution of these data. Additionally, there was a glitch in the System Temperature (Tsys) measurements for the absolute flux calibrator, Juno, necessitating the application of Tsys from another source at different elevation. Together with the inherent uncertainties in the Juno flux density model (it has a large crater), the overall absolute flux density uncertainty is at least 20%.


NOTE: CASA 3.3 is required to follow this guide. For more information on obtaining the latest version of CASA, see [http://casa.nrao.edu http://casa.nrao.edu].
Please include the following acknowledgement in any papers that result from these data: "This paper makes use of public ALMA Science Verification data. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ."
 
==IRAS16293 Band 9 Data Reduction Tutorial==
 
<pre style="background-color: #ffa07a;">
WARNING: On June 15, 2012 these guides were updated to correct for a 1.2" position error in the
phase calibrator (1625-254). Without correction, the science images will suffer from a similar
offset. The final data products (calibrated science data and images) are available at the science
portal as explained above.  
</pre>


==IRAS16293 data tutorials==
The tutorial (called a casaguide) for reducing these data '''using CASA version 6.5.4''' has been split into calibration and imaging pages:


This tutorial has been split into two parts - calibration and imaging:
1) '''[[IRAS16293 Band9 - Calibration]]''' : This section of the tutorial steps you through inspection and calibration of the basic visibility (u-v) data. To complete this part, you will need the data in the first directory: IRAS16293_Band9_UnCalibratedMS.


1) [http://casaguides.nrao.edu/index.php?title=IRAS16293_Band9_-_Calibration '''IRAS16293 Band9 - Calibration'''] : This section of the tutorial steps you through inspection and calibration of the basic visibility (u-v) data. To complete this part, you will need the data in the first directory: IRAS16293_Band9_UnCalibratedMSandTablesForReduction.
2) '''[[IRAS16293 Band9 - Imaging]]''' : This part of the tutorial focuses on constructing images from the fully calibrated visibility data. If you wish to skip calibration and proceed directly to this part of the tutorial, you will need the fully-calibrated visibility data in the IRAS16293_Band9_CalibratedMS directory.


2) [http://casaguides.nrao.edu/index.php?title=IRAS16293_Band9_-_Imaging '''IRAS16293 Band9 - Imaging'''] : This part of the tutorial focuses on constructing images from the fully calibrated visibility data. If you wish to skip calibration and proceed directly to this part of the tutorial, you will need the fully-calibrated visibility data in the IRAS16293_Band9_CalibratedData directory.
'''NOTE: CASA 6.1 or later is required to process the data using the guides above''' (see the [https://casa.nrao.edu/casa_obtaining.shtml CASA download page] to obtain the most recent CASA version).
* The older CASA 6.4 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_6.4]] and [[IRAS16293_Band9_-_Imaging_for_CASA_6.4]]
* The older CASA 6.2 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_6.2]] and [[IRAS16293_Band9_-_Imaging_for_CASA_6.2]]
* The older CASA 6.1 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_6.1]] and [[IRAS16293_Band9_-_Imaging_for_CASA_6.1]]
* The older CASA 5.7 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_5.7]] and [[IRAS16293_Band9_-_Imaging_for_CASA_5.7]]
* The older CASA 5.4 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_5.4]] and [[IRAS16293_Band9_-_Imaging_for_CASA_5.4]]
* The older CASA 5.1 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_5.1]] and [[IRAS16293_Band9_-_Imaging_for_CASA_5.1]]
* The older CASA 4.3 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_4.3]] and [[IRAS16293_Band9_-_Imaging_for_CASA_4.3]]
* The older CASA 4.2 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_4.2]] and [[IRAS16293_Band9_-_Imaging_for_CASA_4.2]]
* The older CASA 4.1 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_4.1]] and [[IRAS16293_Band9_-_Imaging_for_CASA_4.1]]
* The older CASA 4.0 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_4.0]] and [[IRAS16293_Band9_-_Imaging_for_CASA_4.0]]
* The older CASA 3.4 versions of the casaguides are still available at:[[IRAS16293_Band9_-_Calibration_for_CASA_3.4]] and [[IRAS16293_Band9_-_Imaging_for_CASA_3.4]]


We also provide the final continuum and spectral line images in the IRAS16293_Band9_ReferenceImages directory.
We also provide the final continuum and spectral line images in the IRAS16293_Band9_ReferenceImages directory.
Line 85: Line 118:
This color shows you background information about the data or other types of reference material
This color shows you background information about the data or other types of reference material
</pre>
</pre>
{{Checked 3.0.0}}

Latest revision as of 16:02, 17 September 2024


Science Target Overview

IRAS 16293-2422 (d=160 pc; Chini 1981) is a well studied nearby Class 0 proto-binary system (consists of sources A and B) located in L1689 (i.e., Ophiuchus star forming cloud). The projected separation between sources A and B is roughly 5" (Mundy et al. 1992; Chandler et al. 2005; Figure 1 left panel). Sub-arcsecond VLA and SMA centimeter and millimeter/submillimeter continuum images have spatially resolved source A as several components associated with protostars and jets (Chandler et al. 2005; Pech et al. 2010). IRAS 16293-2422 hosts a large-scale quadrupolar outflow (Walker et al. 1988; Mizuno et al. 1990; Castets et al. 2001; Hirano et al. 2001; Garay et al. 2002; Stark et al. 2004; Yeh et al. 2008). The outflow aligned in the east-west direction is currently active and likely originated from source A (Figure 1 right panel). The origin of the other large-scale outflow aligned in the northeast-southwest direction is not clear. Previous molecular line studies with the SMA have revealed detailed structure and kinematics in the circumbinary envelope for each component. These imply gas infall and outflow motions (Chandler et al. 2005; Takakuwa et al. 2007; Yeh et al. 2008). In addition, IRAS 16293-2422 exhibits strong emission from a number of complex organic molecules and other species usually associated with hot cores in massive star-forming regions, especially towards source A (e.g., Blake et al. 1994; van Dishoeck et al. 1995; Bottinelli et al. 2004; Kuan et a. 2004; Schoier et al. 2004; Chandler et al. 2005; Huang et al. 2005; Bisschop et al. 2008; Jorgensen et al. 2011; Caux et al. 2011). Finally, source B shows a narrow line width (Bisschop et al. 2008; Jorgensen et al. 2011) and no clear signature of outflow (Chandler et al. 2005). This suggests that the source may be at the very young evolutionary stage; likely even before the mass accretion/loss processes start.

Fig. 1. Left: Sub-arcsecond continuum image obtained with SMA at 310 GHz by Chandler et al. (2005). Right: Integrated blueshifted and redshifted CO (2-1) image tracing molecular outflow originated from source A. The data were obtained with SMA by Yeh et al. (2008). The emission is integrated over the velocity channels from V_lsr=-7.2 to 3.3 km/s on the blueshifted side and from V_lsr=5.5 to 31.9 km/s on the redshifted side.

ALMA Data Overview

ALMA Science Verification data at Band 9 (602-720 GHz) was taken for IRAS 16293-2422 on April 16 and 17, 2012. The observations have been performed with a seven pointing mosaic centered at RA=16h 32m 22.7s, Dec=-24d28’32.5’’ as shown in Figure 1. The complete 7 pointing mosaic can be seen in Figure 2, superposed on archival SMA data for better visualization.

A scheduling block about 2.3 hours long was run four times for a total of about 9.2 hours of observing time. The integration time of each visibility is 6.048 sec, and the total on-source time of of each pointing is between 16 to 20 min. Three data sets were obtained post-transit, while the other one was obtained pre-transit. The name of the four ASDMs are as follows (with the median value of zenithal precipitable water vapor given in parentheses):

  • uid___A002_X3d4118_X39b (0.31 mm)
  • uid___A002_X3d55cb_X575 (0.65 mm)
  • uid___A002_X3d55cb_Xb50 (0.43 mm)
  • uid___A002_X3d55cb_X90c (0.41 mm)

Data were obtained with the Double Sideband (DSB) Band 9 receivers. Four basebands were used for obtaining data with Frequency Division Mode (FDM). The baseband centers are located at approximately: 704.249, 691.299, 689.499, and 687.499 GHz. The CO (6-5) line at a rest frequency of 691.473 GHz is strongly detected (though extremely resolved out), along with numerous other weaker (but more compact) organic species throughout all four basebands. Each spectral window is 1.875 GHz in width, and contains 3840 channels. The channel separation is 0.488 MHz (0.2 km/s), but the spectral resolution is factor of 2 poorer (0.4 km/s) due to online Hanning smoothing. The image cubes were made with 0.4 km/s channels.

These data were obtained using the Cycle 0 Early Science extended configuration which resulted in an angular resolution of about 0.22"

Fig. 2.Pointings (crosses) and field of view (circles with 9”) for the ALMA band 9 SV observations toward IRAS 16293-2422 overlaid on SMA continuum image at 310 GHz obtained with the extended configuration (angular resolution of 0.97”x0.76”). The SMA data were retrieved from archive. The positions of source Aa, Ab, and B reported in Chandler et al. (2005) are denoted by the black dots.

Using the data for publication: Please use the acknowledgement given at the bottom of the Science Verification Data page.

We thank the following people for suggesting IRAS16293 for ALMA Science Verification: Jes Jorgensen, Suzanne Bisschop, Ewine van Dishoeck, Tyler Bourke, Johan Lindberg, Michiel Hogerheijde, Bill Dent, Martin Zwaan, Al Wootten.

Obtaining the Data

To download all the data, follow one of the next links:

North America

Europe

East Asia

The links provide you with the option to download the following gzipped tar files:

IRAS16293_Band9_UnCalibratedMS - The file contains the raw data files in ALMA Science Data Model (ASDM) format already converted into CASA Measurement Sets (MS) using importasdm inside CASA.

IRAS16293_Band9_CalibratedMS_FIXED - The fully-calibrated u-v data, ready for imaging.

IRAS16293_Band9_ReferenceImages_FIXED - The final continuum and spectral line images.

WARNING: On June 15, 2012 the calibration guide and the final data products (calibrated science 
data: IRAS16293_Band9_CalibratedMS_FIXED.tgz and reference images: IRAS16293_Band9_ReferenceImages_FIXED.tgz)) 
were changed to correct for a 1.2" position error in the phase calibrator (1625-254). Without 
correction, the science images will suffer from a similar offset. 

You can work with these data products at any of the three stages: the UnCalibratedMS, the Calibrated MS (ready for imaging, or the ReferenceImages. Warning: the UnCalibrated data is large.

Caveat: Before using the ReferenceImages for scientific purposes, please note that only a few of the very strongest lines have been excluded from the continuum subtraction or continuum imaging - you may wish to do a more careful job if your science application is strongly dependent on the flux density or morphology of source B, in particular which shows both strong absorption and emission at the 0.2" resolution of these data. Additionally, there was a glitch in the System Temperature (Tsys) measurements for the absolute flux calibrator, Juno, necessitating the application of Tsys from another source at different elevation. Together with the inherent uncertainties in the Juno flux density model (it has a large crater), the overall absolute flux density uncertainty is at least 20%.

Please include the following acknowledgement in any papers that result from these data: "This paper makes use of public ALMA Science Verification data. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ."

IRAS16293 Band 9 Data Reduction Tutorial

WARNING: On June 15, 2012 these guides were updated to correct for a 1.2" position error in the 
phase calibrator (1625-254). Without correction, the science images will suffer from a similar 
offset. The final data products (calibrated science data and images) are available at the science 
portal as explained above. 

The tutorial (called a casaguide) for reducing these data using CASA version 6.5.4 has been split into calibration and imaging pages:

1) IRAS16293 Band9 - Calibration : This section of the tutorial steps you through inspection and calibration of the basic visibility (u-v) data. To complete this part, you will need the data in the first directory: IRAS16293_Band9_UnCalibratedMS.

2) IRAS16293 Band9 - Imaging : This part of the tutorial focuses on constructing images from the fully calibrated visibility data. If you wish to skip calibration and proceed directly to this part of the tutorial, you will need the fully-calibrated visibility data in the IRAS16293_Band9_CalibratedMS directory.

NOTE: CASA 6.1 or later is required to process the data using the guides above (see the CASA download page to obtain the most recent CASA version).

We also provide the final continuum and spectral line images in the IRAS16293_Band9_ReferenceImages directory.

How to Use A CASA Guide

For tips on using CASA and ways CASA can be run, see EVLA_Spectral_Line_Calibration_IRC+10216#How_to_Use_This_casaguide page.

To learn how to extract executable Python scripts from the tutorial, see Extracting_scripts_from_these_tutorials.

Within the guides:

# In CASA
Regions of this color are CASA commands (or definitions) that need to be cut and 
pasted in sequence. Wait until one command is finished before pasting another. 
Tabs matter in python, make sure that commands that span more than one line and 
"for" loops keep their spacing. Sometimes (especially "for" loops) you may need to 
explicitly hit enter twice to get the command going.
Information in this color shows excerpts from the CASA Logger output
This color shows you background information about the data or other types of reference material