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ALMA-IMF Core Working Group, May 06 2021

5/6/2021

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Google doc : https://docs.google.com/document/d/1tnIkhGmBoFEh31udkLDU6WQgOsHq_fA_1QCdcTEKGHY/edit#docs.google.com/document/d/1tnIkhGmBoFEh31udkLDU6WQgOsHq_fA_1QCdcTEKGHY/edit#



Connection:

https://zoom.us/j/92223782076?pwd=K3BlMjdwb2l5KzhGcG9WQ00yVTRVQT09
ID de réunion : 922 2378 2076
Code secret : zZZ7f7



Attendees: 
Not attending:

For memory:
Minutes from our last telecon
Activities of the Core Working Group
Members and their main interests

Agenda:

Debrief on the ALMA-IMF workshop (22 to 26 of March)
Xing: G327 overviewResult: 60-70 cores only.
Cross-matching of getsf versus Gext2D catalogs (40% mismatch!)
Use of MaxLikelihood estimator to check the slope
CMF is flat but depends **a lot** on the temperature you take for cores.
Warning by Yohan: you should adjust the “matching” tolerance according to the beam size of your image. I recommend taking it between 0.5 and 1 time the beam size. This should increase the matching percentage...
Adam: several high-mass core - how are there ~10 cores with ~100 msun?
Friedrich: doubts the sub-fragmentation of the hot core.  Suggests using lines to estimate temperatures (hot cores have plenty of lines with which to do this)   
Sasha: A similar analysis and the same plots must be created for the getsf catalogs. This would show uncertainties of the results. Without comparison of the two methods, the results are difficult to believe.
Jonathan: When the number of cores is small (<100), uncertainties can be significant and bootstrapping is a good technique to assess them (if not obvious, I can explain).
Xing: I will do the same tests with the getsf catalog, thanks for reminding.


Thomas?
Benjamin?

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ALMA-IMF Core Working Group, April 22 2021

4/22/2021

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Connection:

https://zoom.us/j/96841488585?pwd=dURySjB2ZHQ1Z2lnL1FDclJWaTd4QT09
ID de réunion : 968 4148 8585
Code secret : Zw11YV

Google doc :
https://docs.google.com/document/d/1RPZPeDeEo1HrBgN_avnoAnH4OOLOHJ0RZfH2BBPuqrs/edit


Attendees: Sasha, fab,Yohan, Fabrice, Nathalie, Sylvain, Nicolás, Maxime, Thomas, Allison
Not attending: Adam (at CMZOOM), Gemma, Fred

For memory:
Minutes from our last telecon
Activities of the Core Working Group
Members and their main interests

Agenda:

Debrief on the ALMA-IMF workshop (22 to 26 of March)
Mélanie: G012 overviewResult: Gext2D gives higher fluxes than the getsf catalog. Gext2D gives a flatter CMF.
But: Free-free sources were not excluded(?)
Sylvain: A priori they (free-free sources) are removed in the GExt2D source list I sent to you. I remove all sources with Fl_1mm/Fl_3mm < 3.5. This is why sources on the filament seem undetected by GExt2D.
Here is the Fl_1mm vs Fl_3mm for GExt2D all sources for G012.80:


Future goal: look for outflows, especially in the HII region
Friedrich question: Why not using cm maps? Glostar has a too coarse angular resolution. Recombination line are indeed less sensitive.  (Adam’s note: VLA followup data with appropriate resolution, UV coverage are being reduced by UF undergraduate students now)
Pierre D : the difference of the CMF slope between the two extraction is not so important?

Sasha: The differences in CMF slopes (if significant) between the tools are very important for ALMA-IMF and the reasons must be clearly understood. Clearly, some properties of the codes are different. Yohan has the benchmark results for simalma50 and simalma240 for both codes and they must be analyzed in terms of the ratios A/A_true, I/I_true, F/F_true as a function of the S/N ratio I/sigma, as well as a function of the true source size A_true. Such scatter plots are very instructive and I use them a lot in my benchmarking paper. They will help us understand the reasons for the differences in the fluxes and in CMFs. Without such plots and analysis, the reasons cannot be established and this would be very bad, because no clear conclusion would be possible from the CMF work.

Bump in the CMF: denoising might help here, as it permits to extract cores deeper.
Sasha: the difference between the fits of getsf and getext2d are small (1.06 versus 1.17)? Did you try to keep only the common sources?  And for GExt2D, try to include sources even with bad flx_qu because they are detected.

Yohan: concerning the ratio 1/3mm, I recently updated the code to plot ratio as function of S/N to define the most reliable sources to remove. I can re-run G012 to produce this figure or send you the piece of code to do it yourself.

1mm/3mm: permits to separate the free-free contaminated and thermal sources quite efficiently ; perhaps not so efficient when 3mm is hardly detected. Sylvain made tests measuring 3mm fluxes down to 2\sigma -> this is a correct approach if there is a strong 1mm detection at this exact spot (Karl)

Open questions
  1. Who wants to share submited ALMA project?
ALMA Proposal (PI: Nichol Cunningham): two mosaics at high resolution (100 AU) for the central regions of NGC2264 to see the fragmentation cascade (at different scales from the clump size down to the core size)
Fab: none as PI but I was involved in a couple of proposals toward outflows of Class II protostars (trying to know if MHD disk winds are a generic/universal process). One additional proposal toward a massive clump forming at the junction of two large finalements (testing conveyor belt scenario).
  1. Status of the continuum data?
Last data reduction telecon suggested to re-run again continuum maps including the latest re-calibrations done by Luke. It is important to know if we will have a new data release (especially true for core extractions)
Adam: New maps are not expected to change any features of the  continuum data.  I recommend sticking with the current release.
  1. getsf corrections for the sizes and fluxes of the unresolved sources with an overestimated background
if you overestimate the background, the associated component that getsf will substract from the source will be wrong. You will lose some faint parts (the “wings”) leading to a core size smaller than expected. Lot of tests done in benchmarks by Sasha and Yohan suggests that these corrections are improving measurements and mass estimation are closer to the true values.



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ALMA-IMF Core Working Group, April 8 2021

4/8/2021

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Connection:

https://zoom.us/j/99613070931?pwd=U09CY2p3TUVJYnY4UnRoWXU4RHVzdz09
https://zoom.us/j/92684602720?pwd=SXI4UTQ1OTFOSEViYWdRMWxWcmVxUT09
ID de réunion : 926 8460 2720
Code secret : 5y9dHh

Attendees: Fab, Adam, Gemma, Yohan, Nichol, Patricio, Sylvain, Timéa, Maxime, Mélanie, Mélisse, Thomas, Allison, Manuel
Not attending: Fred

For memory:
Minutes from our last telecon
Activities of the Core Working Group
Members and their main interests

Agenda:

  1. Draft of Website for ALMA-IMF (Fab)
Picture
  1. Debrief on the ALMA-IMF workshop (22 to 26 of March)

Draft schedule
2:00 - 2:10: Fabien (global CMF)
2:10 - 2:20: Mélanie (G012)
2:20 - 2:30: Xing (G327)
2:30 - 2:40: Hideaki (G338)
2:40 - 2:50: Yohan (W43-MM2&3)
2:50 - 3:00: Nichol (MnGseg catalogs)
3:00 - 3:10: Theo (protostellar + core models)
3:10 - 3:20: Pierre (PPMAP and Herbie)
3:20 - 3:30: Synthesis: Identifying common tools and objectives

-> coming back on the CMFs in W43-MM2&3 (Yohan)

Questions:
  • Error bars on the CMF; how different from Salpeter in the end?
    • both on the data and on the slope fit
  • Temperature: how drastic is the change with/without PPMAP estimations?
  • Pre versus proto: how do you pinpoint hot cores?
  • How is done the evaluation of completeness?

  1. A word on the outflows, what is the status?
    • Sylvain ?
-> Maxime is handling the code; need to compare the different methods; implementing the PA detection & removing the contamination from nearby sources. Final goal: search massive prestellar core candidates
  • Thomas ?
-> Almost on final state in MM2&3 ; ~50 cores with outflows. The idea is to present them (CO only), no hot-core information. (+perhaps MM1 for statistical reasons: 50 cores is insufficient to derive accurately a core mass function)
  • Allison ?
-> need to get in touch with Thomas to compare the results btw SiO and CO. Ideally a catalogue of the outflows for ALMA-IMF fields ; any evolution with the evolutionary stages ; episodic ejection ?

-> Try and build global pre/proto-stellar CMFs? Search if SiO outflow is an effect of core-mass or of environmental density 

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ALMA-IMF Core Working Group, March 11 2021

3/11/2021

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Connection:
https://univ-grenoble-alpes-fr.zoom.us/j/98634272360?pwd=YkQ1ZVM5K2l4UUFPTkViYVNZRDFXZz09

Attendees: Fred, Sasha, Nathalie, Mélisse, Adam, Sylvain, Allison, Leo, Fabien, Maxime, Mélanie, Nicolas, Fabrice, Nichol, Thomas, Yohan, Karl
Not attending: 

For memory:
Minutes from our last telecon
Activities of the Core Working Group
Members and their main interests


Agenda:

  1. DR and Science workshop on March 22nd-26th
Core WG on Tuesday March 23rd from 2pm to 3:30pm
8 talks of 7min (presentation) + 3min (discussion)

Draft schedule
2:00 - 2:10: Fabien (global CMF)
2:10 - 2:20: Mélanie (G012)
2:20 - 2:30: Xing (G327)
2:30 - 2:40: Hideaki (G338)
2:40 - 2:50: Yohan (W43-MM2&3)
2:50 - 3:00: Nichol (MnGseg catalogs)
3:00 - 3:10: Theo (protostellar + core models)
3:10 - 3:20: Pierre (PPMAP and Herbie)
3:20 - 3:30: Synthesis: Identifying common tools and objectives

  1. News from the CMF and/or Overview 1st papers (Louvet+, Motte+)
    Global CMF results to be discussed on March 23rd.
    The Overview paper shows that the statistics in terms of core content is good-enough to compare massive protoclusters at different evolutionary stages and that there is no observational bias with the total cloud mass or cloud evolutionary stage.



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ALMA-IMF Core Working Group, February 11 2021

2/11/2021

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Connection:
https://univ-grenoble-alpes-fr.zoom.us/j/98634272360?pwd=YkQ1ZVM5K2l4UUFPTkViYVNZRDFXZz09

Attendees: Fred, Timea, Yohan, Sasha, Nathalie, Fabrice, Adam, Ant, Mélisse, Nichol, Thomas, Allison, Sylvain, Gemma, Tapas, Quang
Not attending: 

For memory:
Minutes from our last telecon
Activities of the Core Working Group
Members and their main interests


Agenda:

  1. Catalog filtering, Yohan

  • Filtering out free-free sources from our core catalog
    The 1mm-to-3mm flux ratio with “flux re-scaling” tells us something about the intensity distribution of our core and, possibly, about their prestellar/starless nature.

  • Issues with the correction of continuum fluxes for line contamination
    In the Nature Astronomy paper, for W43-MM1 @ 1.3 mm, this correction was easier because the input images were cleaner/more restrictive:
  • The best-sensitivity image used the SPW7 only ⇒ 1.9 GHz instead of 3.4 GHz (current bsens images)
  • The line-free image used the few SPW7 channels without hot core lines ⇒ 65 MHz instead of 1.4 GHz (W43-MM2 cleanest 1.3 mm image)
Questions: 
  • Nature of the large-diameter cores (Adam) to be investigated
  • What is the difference when identifying free-free sources with their peak flux ratio?
  • Check for any trend in the variation of the sizes with wavelengths and sensitivity
→ plot the re-scale factor in the case of the free-free and hot-core contamination
  • Making aperture photometry or using the same structure observed at 1.3mm to measure the 3mm flux could help confirm the post-selection of free-free sources...

  1. CMF results from the W43-MM2 & MM3 protocluster, Yohan
    CMFs vary depending on the different sub-regions taken.

  1. General questions concerning the W43-MM2&3 dataset

  • Cores name
Timea’s suggestion: ALMAIMF_184736.8-20054.3        (In RA-Dec)
Adam’s suggestion: ALMAIMF_G333.33333+00.3333    (In Galactic coordinates)
Yohan’s suggestion: ALMAIMF_281.86-02.66                      (In degrees)

Picture
  • Yohan used his own continuum images to make the analysis
  • The continuum image of MM2 in B3 differs by 20% in rms (Adam’s version is better than that of Yohan, 4 selfcal iterations instead of 1). [MM3 B3 5 versus 4 selfcal iterations]. 
  • Band 6 images should be similar/the same. Only B6 is used as detection driver.
  • Is it still OK? or shall we redo all the process? from stitching data, applying MnGseg, getsf and Gext2D, analyzing catalogs…

  • Will the `pure-continuum’ image of MM1 or MM2-MM3 be compared to the cleanest image in the Data paper?

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ALMA-IMF Core Working Group, January 28 2021

1/28/2021

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Connection:
https://univ-grenoble-alpes-fr.zoom.us/j/98634272360?pwd=YkQ1ZVM5K2l4UUFPTkViYVNZRDFXZz09

Attendees: Fred, Sasha, Adam, Timea, HongLi, Mélanie, Fabrice, Nichol, Josh, Fabien, Nathalie, Leo, Yohan, Allison, Sylvain, Amy, Cara, Tapas, Mélisse
Not attending: 

For memory:
Minutes from our last telecon
Activities of the Core Working Group
Members and their main interests


Agenda:

  1. Core temperature: News with NH3 fits
    Presentation by Josh Machado (UConn) on W51 NH3 results
NH3, 3’’ → T(NH3) of the cores surrounding (+ ALMA 0.2’’ @ 1mm)
Mean temperatures: 20K (SE or W51-E) 60K (W51-E) up to 120K (W51-IRS2)
Effect of the dynamic assumptions for temperature on the CMF: slightly steeper
Cores located on the extended free-free emission could correspond to chance alignment (no T measurements) or free-free peaks.
To remember: apply for more NH3 measurements at the VLA deadline for C configuration (later than August).

  1. Core extraction softwares: The plus of GExt2D
GExt2D tends to detect more sources (real one from simulated observations) than getsf. → better for clustering studies
getsf seems to provide better flux estimates for the weakest sources. → better for mass studies

  1. CMF results?
  • Fab: I did not examine the new source catalogs (getsf and GExt2D)
  • Yohan: final core catalog (after filtering free-free peaks and correcting for hot core line contamination of the continuum emission) ready → ~200 cores in W43-MM2&MM3
  • Future CMF studies
    Mélanie: G12 (70 sources in cleanest image, most outside the HII region area)
Gemma: W51-E (more sensitive and larger area than the paper to be submitted by Josh+)
Hongli G353.41 (CMF, fragmentation)
Xing G327
    Nichol+Jeff?: on the denoised images by MnGSeg 



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ALMA-IMF Core Working Group, January 14 2021

1/14/2021

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Connection:
https://univ-grenoble-alpes-fr.zoom.us/j/98634272360?pwd=YkQ1ZVM5K2l4UUFPTkViYVNZRDFXZz09

Attendees: Fred, Fabien, Yohan, Sasha, Nathalie, Mélanie, Fabrice, Gemma, Adam, Leo, Sylvain, Amy, Allison, Patricio, Nichol, Timea
Not attending: 

For memory:
Minutes from our last telecon
Activities of the Core Working Group
Members and their main interests


Agenda:
  1. Core extraction softwares: call
→ We need someone to make Dendrogram tests (maybe Roberto & student?)

  1. CMF results on the whole ALMA-IMF sample
  • Fabien’s experience using the Cleanest images of Dec 2020 ⇒ less sources
Global CMF: flatter than Salpeter, independently from their evolutionary stage (at 0 order), generic bias of slope due to projection effect = 0.15 to be taken into account

Automatic removal of (0% in young, 10% in intermediate, ¼ in evolved regions) cores potentially contaminated by free-free emission using 3mm/1mm ratio maps and the recombination line images of Roberto
⇒ Evolutionary stage of regions to be refined (see Fig. 20 of Adam’s paper): G353 and G08 → Intermediate, G12 → Evolved, G337 → Young
⇒ The CMF becomes slightly steeper for evolved regions when removing cores lying in the free-free (H41alpha footprint for now) areas.
Young: G327, G328, G337, G338, W43-MM1, W43-MM2 (no Halpha)
Intermediate: W43-MM3, G351, G353, G008, W51-E (most cores on thermal dust emission)
Evolved: W51-IRS2, G010, G012, G333

The major uncertainty is now coming from the dust temperature, here assumed to be constant over the whole core sample. 
→ Test to be done on W51 using NH3 temperature (Adam + Fabien)

Optical thickness to be investigated, using e.g. the approximated formula of our Nature Astronomy paper.

  • Detailed experience of Yohan on W43-MM2&MM3
Need of rescaling the 3mm flux, use a rms value (2sigma for getsf catalogs) for the 
weak 3mm sources (TBD by Fabien)
    Few sources (2-3) could be free-free in MM3
   

  • Future CMF studies
    Mélanie: G12 (70 sources in cleanest image, most outside the HII region area)
Gemma: W51-E
Hongli G353.41 (CMF, fragmentation)
Xing G327
    Nichol+Jeff?: on the denoised images by MnGSeg 

  1.  Nature of cores: Outflows? Hot cores?
Outflow catalogs will need deep-extraction catalogs to make the association of outflow lobes and lower-mass cores.
To be discussed in 2 weeks.

  1. Core temperature: News with PPMAP? NH3 fits? 
To be discussed in 2 weeks.

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ALMA-IMF Core Working Group, December 17 2020

12/17/2020

0 Comments

 
Connection:
https://univ-grenoble-alpes-fr.zoom.us/j/98634272360?pwd=YkQ1ZVM5K2l4UUFPTkViYVNZRDFXZz09

Attendees: Fred, Fabien, Antoine, Sasha, Adam, Nathalie, Amy, Tapas, Sylvain, Leo, Yohan, Thomas, Jeff, Pierre, Mélisse, Mélanie, Allison, HongLi, Fabrice
Not attending: 

For memory:
Minutes from our last telecon
Activities of the Core Working Group
Members and their main interests


Agenda:
  1. Core extraction softwares: tests on benchmarks using MnGseg or not → Yohan, Fabien, Sylvain, Sasha
When the SNR of core detection decreases the ratio of measured size /true size and measured flux /true flux disperse around the value of 1 → mass estimates are less accurate.
Noise: white noise before simobserve + weather noise in simobserve
Integration time, distance, configuration were supposed to be representing ALMA-IMF images.
→ Dendrogram tests must still be correctly done
→ Comparison of getsf versus Gext2D: good correspondence except for lower-intensity sources

  1. CMF results on the whole ALMA-IMF sample → Fabien
Slightly less sources than in the 1st extraction (Jan 2020)
There is no more evolution of the CMF slope → index = 0.73-0.77 whatever the evolutionary stage of the region, flatter than the slope measure on the IRDC CMF by Patricio.
We now need to take into account free-free sources → removing cores using potential free-free emission (To Be improved), the index all regions gets steeper, and the evolved region close to  = 1.4, the Salpeter index. 
  1.  Outflows arising from cores in W43-MM2→ Thomas
Outflow catalogs will need deep-extraction catalogs to make the association of outflow lobes and lower-mass cores.

  1. PPMAP and Herbie → Pierre Dell’Ova
  • PPMAP (Marsh+2015)
His experience on SNR IC443G images (NIKA2 1-2 mm, LABOCA 870micron, MIPS 160 micron)
Inputs: Data and beam fits for each wavelength + beta and Tdust grids + color correction + “a priori dilution” (1 to 10, effect on Tmap)
Adding 70 micron and even worse 24 micron does not help modelize the SED of the big-grain submm component. Opacity at 70 micron was taken into account (empirical correction) by Ken for the Tdust image of W43-MM1.

  • Herbie (Galliano+2018)
Contains a grain model (THEMIS) but it will require to smooth all data to the worse resolution. It could give information on the dust emissivity and G0 of the global environment, smoothed to 20-40’’. 

None of these models include free-free emission...

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ALMA-IMF Core Working Group, November 5 2020

11/5/2020

0 Comments

 
Connection:
https://univ-grenoble-alpes-fr.zoom.us/j/98634272360?pwd=YkQ1ZVM5K2l4UUFPTkViYVNZRDFXZz09

Attendees: Fred, Sasha, Nathalie, Yohan, Hongli, Mélanie, Ant, Fabien, Fabrice, Adam, Alex, Alison, Antoine, Jeff, Thomas, Patricio, Tapas, Timea
Not attending: Gemma

For memory:
Minutes from our last telecon
Activities of the Core Working Group
Members and their main interests


Agenda:
  1. News on core extraction by Yohan, Fabien and Mélanie
  • Presentation by Mélanie on W33
82 catalogues, 25K assumed, post-selection needed
Preliminary CMF: powerlaw fit? with -1 instead of 1.35 (Salpeter)
Tdust images: PPMAP with validation by modelling of a few sources with Hyperion

→ Hyperion code could be used for the SED fit of 1/ the whole ALMA-IMF fields, when no published luminosity exists (done for W43-MM2) and 2/ some specific cores in our ALMA-IMF fields 

Other people interested to make similar work: 
- Fabrice
- Theo Richardson’s project (PhD with Adam): expanding Robitaille 2017 grid, connecting it with protostellar evolution models

  • Core catalogs
Catalogs done with getsf → catalogs to be investigated
With Getx2D, significance still need to be investigated before catalogs are made
Nothing done for Dendrogram yet
→ Benchmark images to be used
→ Need to contact Erik for Dendrograms

  1. Temperature estimates with PPMAP

  • The PPMAP procedure 
Default run:
  • with ALMA B6 and B3 + Herschel 70, 160, 250 micron + SABOCA 350 micron + LABOCA 870 micron
  • with 60’’-filtered images
  • using a ‘tight noise’ weighting of the SED fit.
Several runs: 
  • the Herschel-only run → to be used
  • ALMA, no filtering → issue with the edges of ALMA images (too high temperatures)
  • ALMA B6 + NOEMA 3mm (equiv 7M ALMA B3) instead ALMA B3 (bad fit close to the HII region + more NANs) no filtering → same, issue with the edges of ALMA images (too high temperatures)
  • ALMA B6 + NOEMA 3mm with filtering → resembles the run with B3, B6 edges are causing problems
  • Default run with optical depth corrections soon

Questions
  • Could we fit SEDs on each pixel just dropping the negative flux?
  • A combination of the 2 resulting images… 

PPMAP experts:
→ Ken Marsh (IPAC) and Alex Howard (in a company from Monday on)
→ Matt Smith from Cardiff (extragalactic focus)
→ Ana XX (SNR astronomer)
→ Hands-on? Interested people: 
From France: Fabrice Herpin, Fred, Yohan, Antoine, Mélanie?, 
From US: Allison Towner, Adam
From Mexico: Thomas?



  • Jeff’s evaluation of the filtering scales of the datasets used by PPMAP 
Jeff’s presentation from 4 weeks ago.
Not discussed today...


  1. Other estimations of the core temperature
Not discussed today
  • Status of Brian’s efforts to analyze and collect ammonia data

  • Fred and Nathalie should soon present the proxy proposed for the protostellar luminosity of continuum cores, using the “line contamination” of “the continuum band” by COMs lines.

0 Comments

ALMA-IMF Core Working Group, October 15 2020

10/15/2020

0 Comments

 
Connection:
https://ufl.zoom.us/j/96368629056?pwd=c1JmbWN6Rll0ZkNjYzJZamtXZFdmUT09

Attendees: Fred, Yohan, Adam, Timea, Sasha, Gemma, Allison, Hongli, Roberto, Alex, Ant, Nathalie, Amy, Fabien, Tapas
Not attending: Manuel

For memory:
Minutes from our last telecon
Members and their main interests


Agenda:
  1. Temperature estimates with PPMAP

  • The PPMAP procedure to estimate the Tdust image of ALMA-IMF fields
Alex’s slides

  • Herschel-only (14’’-resolution, no filtering) run
Bands (in micron): 70, 160, 250, 350 (Herschel), 500
→ to be used as a model toward which the high-resolution Tdust images should converge

  • Run with 60’’-filtered maps (2.5’’-resolution, B3 filtering, without Herschel 500)
Bands (in micron): 70, 160, 250, 350 (SABOCA), 870, 1300, 3000
  • Many pixels are not fitted because of negative levels created by the filtering process or because of noise in the ALMA (especially B3) images. → Lots of/Too many NANs.
  • The SED fits of the main peaks (MM2 and MM3) still diverge at the LABOCA 870 and ALMA 1300 and 3000 micron wavelengths. → Change the weights?
  • The ‘half noise’ and ‘tight noise’ runs try to compensate for the poor noise levels of the submm images: 
Half noise: sigma/2 for LABOCA (870), ALMA B6 (1300), and ALMA B3 (3000).
Tight noise: sigma/2 for LABOCA (870) and ALMA B3 (3000); sigma/4 for ALMA B6 (1300).
Gaussian noise is assumed and levels are calculated for each map as a first step of PPMAP. These noise levels are used in the SED fit. 
The effect of a non-Gaussian noise on the PPMAP results should be checked… If we were to impose some weights for the different wavelengths, PPMAP would need to be modified. → not for now!
Temperature increases from the ‘normal noise’ to ‘half noise’ and the ‘tight noise’ runs. Be careful! The “tight noise” run gives temperatures closer to that of the Herschel run. 

  • Run with 30’’-filtered maps (2.5’’-resolution, B6 filtering, without SABOCA?)
Bands (in micron): 70, 160, 250, 350 (SABOCA), 870, 1300, 3000
The SED fit gets worse to the 70 micron point and a s a consequence the small heating toward MM2 is lost → the 60’’-filtering run seems more reasonable

  • Run without the B3 data
Bands (in micron): 70, 160, 250, 350 (SABOCA), 870, 1300
  • When the ‘free-free-contaminated’ B3 image is ignored, the Tdust image displays less cold values at the location of the HII region (18K instead of 13K) and of the filament (23K instead of 18K) lying below the HII region. → To be checked if this map would be better to estimate the temperature of cores lying over this filament…
  • There are less NANs suggesting that a SED fit should be allowed when either the B6 or B3 image has negative pixels.

Preliminary conclusions:
→ The 60’’-filtering run seems better than the 30’’-filtering run
→ The ‘tight noise’ run gives temperature in the background that better corresponds to that of the Herschel run.
→ The run without B3 gives better Tdust values close to/but off the HII region.
→ Could we combine the Herschel-only map and 60’’-filtering ‘tight-noise’ map to have a continuous Tdust image? Could we fit SEDs on each pixel just dropping the negative flux?


  • Jeff’s evaluation of the filtering scales of the datasets used by PPMAP 
Jeff’s presentation from 2 weeks ago.
Not discussed today

  1. News on core extraction by Yohan and Fabien
Not discussed today

  1. Other estimations of the core temperature
Not discussed today
  • Status of Brian’s efforts to analyze and collect ammonia data

  • Fred and Nathalie should soon present the proxy proposed for the protostellar luminosity of continuum cores, using the “line contamination” of “the continuum band” by COMs lines.

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