Cold Cores
Cold clumps and cold cores
The terms cold clumps and cold cores refer to dense and cold regions
within interstellar molecular clouds. Clumps are typically larger than
0.1 pc and may contain further substructure. Cores are more compact,
typically bound by gravity. The cores can collapse under their own
self-gravity and thus form new stars. Prior to star-formation the
objects are cold because they contain a lot of dust that shields the
cores and clumps from the external heating by stars and, on the other
hand, the interstellar medium cools via the radiation of the dust and
of the molecules.
Cold cores also refers to the research projects that were conducted
using the Planck and Herschel satellites. Planck mapped the whole sky
at several submillimetre wavelengths. The observations were used to
locate over 13000 cold objects all over the Milky Way. These are
either clouds that may in the future form new stars or they may also
be dense regions within already star-forming clouds. The Planck
Galactic catalogue of Cold Clumps (PGCC) is described in the paper
Planck Collaboration 2016: Planck 2015 results
XXVIII
.
The Herschel satellite was launched at the same time with Planck. It
had a much higher spatial resolution than Planck and it also covered
partly shorter wavelengths. We had an open time key programme Galactic
Cold Cores which used Herschel for dedicated follow-up observations of
the Planck clumps. This
search
will return most of the papers
published on the analysis of those observations.
Cold Cores meetings
Annual meetings of the Cold Cores project
The Cold Cores project has had annual meetings and teleconferences since 2010. The program and
presentations of the latest meetings can be found following the links below.
Cold Cores teleconferences
We have held over the years semi-regular teleconferences. Since late 2020, these have been organised as
video conferences, often also including one talk. The following list contains some of
these presentations.
- 19.2.2021, Timothé Roland: Dynamics of stellar structures emerging from star forming regions
- 29.3.2021, Nathalie Ysard: Dust evolution towards dense interstellar regions
- 11.3.2022, Tie Liu: ATOMS and ALMASOP: present status and future plans
- 19.4.2022, Zujia Lu: The Dynamical State of Star-forming Regions, from Molecular Clouds to Massive Clumps
- 16.11.2022, Emma Mannfors: Filaments on OMC-3
- 22.12.2022, Kate Pattle: Connecting Magnetic Fields and Stellar Feedback with JCMT POL-2
- 24.2.2023, Mika Juvela: Filaments in the OMC-3 cloud: MIR extinction
- 27.11.2023, Job Vorster: B-FROST: Combining Multiple Perspectives on Gravitational Stability in MBM12
- 6.2.2024, Jonathan Oers: Statistical analysis of the relative orientation between filaments and magnetic fields in the GCC fields
- 28.3.2024, Dana Alina: Magnetic field of the Ring-like molecular cloud G111: update from polarization data analysis
- 25.9.2024, Job Vorster: Identifying mechanisms of water maser variability during the
accretion burst in NGC6334I
- 13.11.2024, Derek Ward-Thompson: Latest Results From The JCMT BISTRO Survey - Can B-fields explain why star formation is so inefficient?
Cold Cores publications
The list below contains some of the papers published as part of the cold cores
project.
- Juvela M., Malinen J., Montillaud J., et al., 2018, Galactic cold
cores. IX. Column density structures and radiative-transfer
modelling
,
Astronomy & Astrophysics 614, A83
- Rivera-Ingraham A., Ristorcelli I., Juvela M., et al., 2017,
Galactic cold cores. VIII. Filament formation and evolution: Filament
properties in context with evolutionary
models
,
Astronomy & Astrophysics 601, A94
- Rivera-Ingraham A., Ristorcelli I., Juvela, M., et al., 2016,
Galactic cold cores. VII. Filament formation and evolution: Methods
and observational
constraints
,
Astronomy & Astrophysics 591, A40
- Juvela M., Demyk K., Doi Y., et al., 2015, Galactic cold cores. VI.
Dust opacity spectral
index
,
Astronomy & Astrophysics 584, A94
- Juvela M., Ristorcelli I., Marshall D. J., et al., 2015, Galactic
cold cores. V. Dust
opacity
,
Astronomy & Astrophysics 584, A93
- Montillaud J., Juvela M., Rivera-Ingraham A., et al., 2015,
Galactic cold cores. IV. Cold submillimetre sources: catalogue and
statistical
analysis
,
Astronomy & Astrophysics 584, A92
- Juvela M., Ristorcelli I., Pagani, L., et al., 2012,
Galactic cold cores. III. General cloud
properties
,
Astronomy & Astrophysics 541, A12
- Juvela M., Ristorcelli I., Pelkonen V.-M., et al., 2011,
Galactic cold cores. II. Herschel study of the extended dust emission
around the first Planck
detections
,
Astronomy & Astrophysics 527, A111
- Juvela M., Ristorcelli I., Montier L.A., et al., 2010,
Galactic cold cores: Herschel study of first Planck
detections
,
Astronomy & Astrophysics 518, L93
- Planck 2015 results. XXVIII. The Planck Catalogue of Galactic cold
clumps
,
Astronomy & Astrophysics 594, A28
- Planck early results. XXIII. The first all-sky survey of Galactic
cold
clumps
,
2011, Astronomy & Astrophysics, Volume 536, A23,
- Planck early results. XXII. The submillimetre properties of a
sample of Galactic cold
clumps
,
2011, Astronomy & Astrophysics, Volume 536, A22
- Montier L.A., Pelkonen V.-M., Juvela M., Ristorcelli I., Marshall,
D.J., An all-sky catalogue of cold cores observed with Planck-HFI:
simulation and colour detection
algorithms
,
2010, Astronomy & Astrophysics, Volume 522, A83
Below are some further theoretical papers that were related to the
work on the cold cores.
- Juvela M., Padoan P., Ristorcelli I., Pelkonen V.-M., 2019,
Synthetic observations of dust emission and polarisation of Galactic
cold clumps
,
Astronomy & Astrophysics 629, A63
- Juvela M., 2016,
Template matching method for the analysis of interstellar cloud
structure
,
Astronomy & Astrophysics 593, A58
- Juvela M., Montillaud J., 2016, Near-infrared extinction with
discretised stellar
colours
,
Astronomy & Astrophysics 585, A78
- Juvela M., Montillaud J., 2016,
Allsky NICER and NICEST extinction maps based on the 2MASS
near-infrared survey
,
Astronomy & Astrophysics 585, A38
- Juvela M., Montillaud J., 2013,
Estimation of high-resolution dust column density maps. Empirical
model
fits
,
Astronomy & Astrophysics 557, A73
- Juvela M., Montillaud J., Ysard N., Lunttila, T., 2013,
The degeneracy between dust colour temperature and spectral index.
Comparison of methods for estimating the β(T)
relation
,
Astronomy & Astrophysics 556, A63
- Juvela M., Malinen J., Lunttila, T., 2013, Estimation of
high-resolution dust column density maps. Comparison of modified
black-body fits and radiative transfer
modelling
,
Astronomy & Astrophysics 553, A113
- Juvela M., Malinen J., Lunttila T., 2012,
Profiles of interstellar cloud filaments. Observational effects in
synthetic sub-millimetre
observations
,
Astronomy & Astrophysics 544, A141
- Juvela M., Ysard N., 2012,
The degeneracy between the dust colour temperature and the spectral
index. The problem of multiple χ2
minima
,
Astronomy & Astrophysics 541, A33
- Juvela M., Ysard N., 2012,
The effect of temperature mixing on the observable (T, β)-relation of
interstellar dust
clouds
,
Astronomy & Astrophysics 539, A71
- Juvela M., Harju J., Ysard N., Lunttila, T., 2012, Reliability of NH3 as the
temperature probe of cold cloud
cores
,
Astronomy & Astrophysics 538, A133
- Juvela M., Ysard N., 2011,
On the Gas Temperature of Molecular Cloud
Cores
,
Astronomy & Astrophysics 739, A63