arXiv subjects

Suzanne Madden

Publications and source records attributed to Suzanne Madden.

At least 19 recordsLinked to original sources

arXiv2025

A wide-field, multi-line survey of CO in the Magellanic Clouds at parsec-scale resolution: characterising the molecular gas content with a 50-m single-dish submillimeter telescope

The Large and Small Magellanic Clouds (LMC, SMC) are nearby dwarf galaxies whose proximity uniquely enables molecular cloud-scale resolution observations across the entire Magellanic system, a capability unmatched in any other external galaxy. Their low metallicities resemble conditions near the peak of cosmic star formation, allowing resolved studies of interstellar medium (ISM) phases, molecular cloud lifecycles, and feedback processes that regulate galaxy evolution. Comprehensive, wide-field spectroscopic mapping of CO and its isotopologues in different transitions, complemented by [CI] observations, and combined with already existing HI and HII surveys, will calibrate star-formation laws and gas-phase partition under low-metallicity conditions and furnish benchmarks for interpreting high-redshift galaxies and cosmological simulations. This science requires a large-aperture, wide-field submillimeter single dish with multi-pixel spectroscopic capabilities, operated from a high, dry site such as Chajnantor, to deliver fast, sensitive, high-resolution, degree-scale mapping with total-power fidelity. We present the case for a full molecular atlas of the Magellanic system, the enabling facility requirements, and the transformative impact on galaxy evolution studies

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arXiv2025

PRIMA survey of the Virgo cluster

Clusters of galaxies are unique laboratories for investigating the dependence of galaxy evolution on their environment. The Herschel Virgo Cluster Survey (HeViCS) mapped the central 84 square degrees region of the Virgo Cluster in five bands between 100 and 500 micron, which resulted in the first detailed view of cold dust in cluster galaxies. Major limitations of the HeViCS survey were the lack of data, or its limited availability, in the 20 to 80 micron range, and the quite low sensitivity of the Photodetector Array Camera and Spectrometer instrument, resulting in poor constraints on the warmer dust component. The PRIMAger instrument onboard PRIMA offers the capability to map a large portion of the Virgo Cluster -- including regions beyond its virial radius -- in hyperspectral and polarimetric bands from 25 to 265 micron, enabling a direct comparison with the area previously covered by HeViCS. By combining PRIMA and Herschel data with existing multi-wavelength photometry, it becomes possible to explore the connection between stellar and dust properties in a complete sample of cluster galaxies, to investigate environmental effects on the warm dust component within the Virgo Cluster, to map the magnetic field structure of the cold interstellar medium (ISM), to search for dust emission from the intra-cluster medium, and to study the ISM in background galaxies projected behind the cluster.

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arXiv2025

The PRIMA promise of deciphering interstellar dust evolution with observations of the nearby Universe

This paper develops a few science cases, using the PRIMA far-IR probe, aimed at achieving several breakthroughs in our understanding of the dust properties and their evolution. We argue that the specific observational capabilities of PRIMA, namely its unprecedented sensitivity over the whole far-IR range and the possibility to obtain continuous spectra between wavelengths 24 and 235 microns, are essential to progress in our understanding of the physics of the interstellar medium and galaxy evolution. Our science cases revolve around observations of nearby galaxies. We discuss the importance of detecting the IR emission of the diffuse interstellar medium of these galaxies, including very low-metallicity systems. We also discuss the opportunity of detecting various solid-state features to understand the mineralogy of interstellar grains. Finally, we stress the unique opportunity brought by the possible simultaneous measures of both the dust continuum and the far-IR fine-structure gas lines. These science cases could be distributed in a few large programs.

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arXiv2024

A radial decrease in kinetic temperature measured with formaldehyde in 30 Doradus

Feedback from star formation is a critical component of the evolution of galaxies and their interstellar medium. At parsec scales internal to molecular clouds, however, the observed signatures of that feedback on the physical properties of CO-emitting gas have often been weak or inconclusive. We present sub-parsec observations of H2CO in the 30 Doradus region, which contains the massive star cluster R136 that is clearly exerting feedback on its neighboring gas. H2CO provides a direct measure of gas kinetic temperature, and we find a trend of decreasing temperature with projected distance from R136 that may be indicative of gas heating by the stars. While it has been suggested that mechanical heating affects H2CO-measured temperature, we do not observe any correlation between TK and line width. The lack of an enhancement in mechanical feedback close to R136 is consistent with the absence of a radial trend in gravitational boundedness seen the ALMA CO observations. Estimates of cosmic ray flux in the region are quite uncertain but can plausibly explain the observed temperatures, if R136 itself is the dominant local source of energetic protons. The observations presented here are also consistent with the H2CO-emitting gas near R136 being dominated by direct radiation from R136 and photoelectric heating in the photodissociation regions.

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arXiv2022

The resolved scaling relations in DustPedia: Zooming in on the local Universe

We perform a homogeneous analysis of an unprecedented set of spatially resolved scaling relations (SRs) between ISM components and other properties in the range of scales 0.3-3.4 kpc. We also study some ratios: dust-to-stellar, dust-to-gas, and dust-to-metal. We use a sample of 18 large, spiral, face-on DustPedia galaxies. All the SRs are moderate/strong correlations except the dust-HI SR that does not exist or is weak for most galaxies. The SRs do not have a universal form but each galaxy is characterized by distinct correlations, affected by local processes and galaxy peculiarities. The SRs hold starting from 0.3 kpc, and if a breaking down scale exists it is < 0.3 kpc. By evaluating all galaxies at 3.4 kpc, differences due to peculiarities of individual galaxies are cancelled out and the corresponding SRs are consistent with those of whole galaxies. By comparing subgalactic and global scales, the most striking result emerges from the SRs involving ISM components: the dust-total gas SR is a good correlation at all scales, while the dust-H2 and dust-HI SRs are good correlations at subkpc/kpc and total scales, respectively. For the other explored SRs, there is a good agreement between small and global scales and this may support the picture where the main physical processes regulating the properties and evolution of galaxies occur locally. Our results are consistent with the hypothesis of self-regulation of the SF process. The analysis of subgalactic ratios shows that they are consistent with those derived for whole galaxies, from low to high z, supporting the idea that also these ratios could be set by local processes. Our results highlight the heterogeneity of galaxy properties and the importance of resolved studies on local galaxies in the context of galaxy evolution. They also provide observational constraints to theoretical models and updated references for high-z studies.

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arXiv2022

Infrared view of the multiphase ISM in NGC 253 I. Observations and fundamental parameters of the ionised gas

Context. Massive star-formation leads to enrichment with heavy elements of the interstellar medium. On the other hand, the abundance of heavy elements is a key parameter to study the star-formation history of galaxies. Furthermore, the total molecular hydrogen mass, usually determined by converting CO or [C ii] 158 $μ$m luminosities, depends on the metallicity as well. The excitation of metallicity-sensitive emission lines, however, depends on the gas density of H ii regions, where they arise. Aims. We used spectroscopic observations from SOFIA, Herschel, and Spitzer of the nuclear region of the starburst galaxy NGC 253, as well as photometric observations from GALEX, 2MASS, Spitzer, and Herschel in order to derive physical properties such as the optical depth to correct for extinction, as well as the gas density and metallicity of the central region. Methods. Ratios of the integrated line fluxes of several species were utilised to derive the gas density and metallicity. The [O iii] along with the [S iii] and [N ii] line flux ratios for example, are sensitive to the gas density but nearly independent of the local temperature. As these line ratios trace different gas densities and ionisation states, we examined if these lines may originate from different regions within the observing beam. The ([Ne ii] 13 $μ$m + [Ne iii] 16 $μ$m)/Hu $α$ line flux ratio on the other hand, is independent of the depletion onto dust grains but sensitive to the Ne/H abundance ratio and will be used as a tracer for metallicity of the gas. Results. We derived values for gas phase abundances of the most important species, as well as estimates for the optical depth and the gas density of the ionised gas in the nuclear region of NGC 253. We obtained densities of at least two different ionised components $(< 84$ cm$^{-3}$ and $\sim 170 - 212$ cm$^{-3})$ and a metallicity of solar value.

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arXiv2021

Sub-millimetre compactness as a critical dimension to understand the Main Sequence of star-forming galaxies

We study the interstellar medium (ISM) properties as a function of the molecular gas size for 77 infrared-selected galaxies at $z \sim 1.3$. Molecular gas sizes are measured on ALMA images that combine CO(2-1), CO(5-4) and underlying continuum observations, and include CO(4-3), CO(7-6)+[CI]($^3 P_2-^3P_1$), [CI]($^3 P_1-^3P_0$) observations for a subset of the sample. The $\gtrsim 46 \%$ of our galaxies have a compact molecular gas reservoir, and lie below the optical disks mass-size relation. Compact galaxies on and above the main sequence have higher CO excitation and star formation efficiency than galaxies with extended molecular gas reservoirs, as traced by CO(5-4)/CO(2-1) and CO(2-1)/$L_{\rm IR, SF}$ ratios. Average CO+[CI] spectral line energy distributions indicate higher excitation in compacts relative to extended sources. Using CO(2-1) and dust masses as molecular gas mass tracers, and conversion factors tailored to their ISM conditions, we measure lower gas fractions in compact main-sequence galaxies compared to extended sources. We suggest that the sub-millimetre compactness, defined as the ratio between the molecular gas and the stellar size, is an unavoidable information to be used with the main sequence offset to describe the ISM properties of galaxies, at least above $M_{\star} \geqslant 10^{10.6}$ M$_{\odot}$, where our observations fully probe the main sequence scatter. Our results are consistent with mergers driving the gas in the nuclear regions, enhancing the CO excitation and star formation efficiency. Compact main-sequence galaxies are consistent with being an early post-starburst population following a merger-driven starburst episode, stressing the important role of mergers in the evolution of massive galaxies.

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arXiv2019

Structural and Dynamical Analysis of 0.1pc Cores and Filaments in the 30~Doradus-10 Giant Molecular Cloud

High-resolution ($<$0.1pc) ALMA observations of the 30Dor-10 molecular cloud 15pc north of R136 are presented. The $^{12}$CO 2-1 emission morphology contains clumps near the locations of known mid-infrared massive protostars, as well as a series of parsec-long filaments oriented almost directly towards R136. There is elevated kinetic energy (linewidths at a given size scale) in 30Dor-10 compared to other LMC and Galactic star formation regions, consistent with large scale energy injection to the region. Analysis of the cloud substructures is performed by segmenting emission into disjoint approximately round "cores" using clumpfind, by considering the hierarchical structures defined by isointensity contours using dendrograms, and by segmenting into disjoint long thin "filaments" using Filfinder. Identified filaments have widths $\sim$0.1pc. The inferred balance between gravity and kinematic motions depends on the segmentation method: Entire objects identified with clumpfind are consistent with free-fall collapse or virial equilibrium with moderate external pressure, whereas many dendrogram-identified parts of hierarchical structures have higher mass surface densities $Σ_{LTE}$ than if gravitational and kinetic energies were in balance. Filaments have line masses that vary widely compared to the critical line mass calculated assuming thermal and nonthermal support. Velocity gradients in the region do not show any strong evidence for accretion of mass along filaments. The upper end of the "core" mass distribution is consistent with a power-law with the same slope as the stellar initial mass function.

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arXiv2019

An ALMA view of molecular filaments in the Large Magellanic Cloud II: An early stage of high-mass star formation embedded at colliding clouds in N159W-South

We have conducted ALMA CO isotopes and 1.3 mm continuum observations toward filamentary molecular clouds of the N159W-South region in the Large Magellanic Cloud with an angular resolution of $\sim$0"25 ($\sim$0.07 pc). Although the previous lower-resolution ($\sim$1") ALMA observations revealed that there is a high-mass protostellar object at an intersection of two line-shaped filaments in $^{13}$CO with the length scale of $\sim$10 pc, the spatially resolved observations, in particular, toward the highest column density part traced by the 1.3 mm continuum emission, the N159W-South clump, show complicated hub-filamentary structures. We also discovered that there are multiple protostellar sources with bipolar outflows along the massive filament. The redshifted/blueshifted components of the $^{13}$CO emission around the massive filaments/protostars have complementary distributions, which is considered to be a possible piece of evidence for a cloud-cloud collision. We propose a new scenario in which the supersonically colliding gas flow triggers the formation of both the massive filament and protostars. This is a modification of the earlier scenario of cloud-cloud collision, by Fukui et al., that postulated the two filamentary clouds occur prior to the high-mass star formation. A recent theoretical study of the shock compression in colliding molecular flows by Inoue et al. demonstrates that the formation of filaments with hub structure is a usual outcome of the collision, lending support for the present scenario. The theory argues that the filaments are formed as dense parts in a shock compressed sheet-like layer, which resembles $"$an umbrella with pokes.$"$

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arXiv2019

An ALMA view of molecular filaments in the Large Magellanic Cloud I: The formation of high-mass stars and pillars in the N159E-Papillon Nebula triggered by a cloud-cloud collision

We present the ALMA observations of CO isotopes and 1.3 mm continuum emission toward the N159E-Papillon Nebula in the Large Magellanic Cloud (LMC). The spatial resolution is 0"25-0"28 (0.06-0.07 pc), which is a factor of 3 higher than the previous ALMA observations in this region. The high resolution allowed us to resolve highly filamentary CO distributions with typical widths of $\sim$0.1 pc (full width half maximum) and line masses of a few 100 $M_{\odot}$ pc$^{-1}$. The filaments (more than ten in number) show an outstanding hub-filament structure emanating from the nebular center toward the north. We identified for the first time two massive protostellar outflows of $\sim$10$^4$ yr dynamical age along one of the most massive filaments. The observations also revealed several pillar-like CO features around the Nebula. The H II region and the pillars have a complementary spatial distribution and the column density of the pillars is an order of magnitude higher than that of the pillars in the Eagle nebula (M16) in the Galaxy, suggesting an early stage of pillar formation with an age younger than $\sim$10$^5$ yr. We suggest that a cloud-cloud collision triggered the formation of the filaments and protostar within the last $\sim$2 Myr. It is possible that the collision is more recent, as part of the kpc-scale H I flows come from the tidal interaction resulting from the close encounter between the LMC and SMC $\sim$200 Myr ago as suggested for R136 by Fukui et al.

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arXiv2019

Radiative and mechanical feedback into the molecular gas in the Large Magellanic Cloud. II. 30 Doradus

With an aim of probing the physical conditions and excitation mechanisms of warm molecular gas in individual star-forming regions, we performed Herschel SPIRE FTS observations of 30 Doradus in the LMC. In our FTS observations, important FIR cooling lines in the ISM, including CO J=4-3 to 13-12, [CI] 370 micron, and [NII] 205 micron, were clearly detected. In combination with ground-based CO data, we then constructed CO spectral line energy distributions (SLEDs) on 10 pc scales over a 60 pc x 60 pc area and found that the shape of the observed CO SLEDs considerably changes across 30 Doradus, e.g., the peak transition varies from J=6-5 to 10-9, while the slope characterized by the high-to-intermediate J ratio ranges from 0.4 to 1.8. To examine the source(s) of these variations in CO transitions, we analyzed the CO observations, along with [CII] 158 micron, [CI] 370 micron, [OI] 145 micron, H2 0-0 S(3), and FIR luminosity data, using state-of-the-art models of PDRs and shocks. Our detailed modeling showed that the observed CO emission likely originates from highly-compressed (thermal pressure ~ 1e7-1e9 K cm-3) clumps on 0.7-2 pc scales, which could be produced by either UV photons (UV radiation field ~ 1e3-1e5 Mathis fields) or low-velocity C-type shocks (pre-shock medium density ~ 1e4-1e6 cm-3 and shock velocity ~ 5-10 km s-1). Considering the stellar content in 30 Doradus, however, we tentatively excluded the stellar origin of CO excitation and concluded that low-velocity shocks driven by kpc scale processes (e.g., interaction between the Milky Way and the Magellanic Clouds) are likely the dominant source of heating for CO. The shocked CO-bright medium was then found to be warm (temperature ~ 100-500 K) and surrounded by a UV-regulated low pressure component (a few (1e4-1e5) K cm-3) that is bright in [CII] 158 micron, [CI] 370 micron, [OI] 145 micron, and FIR dust continuum emission.

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arXiv2016

The dustier early-type galaxies deviate from late-type galaxies' scaling relations

Several dedicated surveys focusing on early-type galaxies (ETGs) reveal that significant fractions of them are detectable in all interstellar medium phases studied to date. We select ETGs from the Herschel Reference Survey that have both far-infrared Herschel and either HI or CO detection (or both). We derive their star formation rates (SFR), stellar masses and dust masses via modelling their spectral energy distributions. We combine these with literature information on their atomic and molecular gas properties, in order to relate their star formation, total gas mass and dust mass on global scales. The ETGs deviate from the dust mass-SFR relation and the Schmidt-Kennicutt relation that SDSS star forming galaxies define: compared to SDSS galaxies, ETGs have more dust at the same SFR, or less SFR at the same dust mass. When placing them in the M*-SFR plane, ETGs show a much lower specific SFR as compared to normal star-forming galaxies. ETGs show a large scatter compared to the Schmidt-Kennicutt relation found locally within our Galaxy, extending to lower SFRs and gas mass surface densities. Using an ETG's SFR and the Schmidt-Kennicutt law to predict its gas mass leads to an underestimate. ETGs have similar observed-gas-to-modelled-dust mass ratios to star forming-galaxies of the same stellar mass, as well as they exhibit a similar scatter.

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arXiv2016

Radiative and mechanical feedback into the molecular gas in the Large Magellanic Cloud. I. N159W

We present Herschel SPIRE Fourier Transform Spectrometer (FTS) observations of N159W, an active star-forming region in the Large Magellanic Cloud (LMC). In our observations, a number of far-infrared cooling lines including CO(4-3) to CO(12-11), [CI] 609 and 370 micron, and [NII] 205 micron are clearly detected. With an aim of investigating the physical conditions and excitation processes of molecular gas, we first construct CO spectral line energy distributions (SLEDs) on 10 pc scales by combining the FTS CO transitions with ground-based low-J CO data and analyze the observed CO SLEDs using non-LTE radiative transfer models. We find that the CO-traced molecular gas in N159W is warm (kinetic temperature of 153-754 K) and moderately dense (H2 number density of (1.1-4.5)e3 cm-3). To assess the impact of the energetic processes in the interstellar medium on the physical conditions of the CO-emitting gas, we then compare the observed CO line intensities with the models of photodissociation regions (PDRs) and shocks. We first constrain the properties of PDRs by modelling Herschel observations of [OI] 145, [CII] 158, and [CI] 370 micron fine-structure lines and find that the constrained PDR components emit very weak CO emission. X-rays and cosmic-rays are also found to provide a negligible contribution to the CO emission, essentially ruling out ionizing sources (ultraviolet photons, X-rays, and cosmic-rays) as the dominant heating source for CO in N159W. On the other hand, mechanical heating by low-velocity C-type shocks with ~10 km/s appears sufficient enough to reproduce the observed warm CO.

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arXiv2016

Kinematic Structure of Molecular Gas around High-mass Star YSO, Papillon Nebula, in N159 East in the Large Magellanic Cloud

We present the ALMA Band 3 and Band 6 results of 12CO(2-1), 13$CO(2-1), H30alpha recombination line, free-free emission around 98 GHz, and the dust thermal emission around 230 GHz toward the N159 East Giant Molecular Cloud (N159E) in the Large Magellanic Cloud (LMC). LMC is the nearest active high-mass star forming face-on galaxy at a distance of 50 kpc and is the best target for studing high-mass star formation. ALMA observations show that N159E is the complex of filamentary clouds with the width and length of ~1 pc and 5 pc - 10 pc, respectively. The total molecular mass is 0.92 x 10^5 Msun from the 13CO(2-1) intensity. N159E harbors the well-known Papillon Nebula, a compact high-excitation HII region. We found that a YSO associated with the Papillon Nebula has the mass of 35 Msun and is located at the intersection of three filamentary clouds. It indicates that the formation of the high-mass YSO was induced by the collision of filamentary clouds. Fukui et al. 2015 reported a similar kinematic structure toward a YSO in the N159 West region which is another YSO that has the mass larger than 35 Msun in these two regions. This suggests that the collision of filamentary clouds is a primary mechanism of high-mass star formation. We found a small molecular hole around the YSO in Papillon Nebula with sub-pc scale. It is filled by free-free and H30alpha emission. Temperature of the molecular gas around the hole reaches ~ 80 K. It indicates that this YSO has just started the distruction of parental molecular cloud.

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arXiv2015

Herschel Spectroscopic Observations of LITTLE THINGS Dwarf Galaxies

We present far-infrared spectral line observations of five galaxies from the LITTLE THINGS sample: DDO 69, DDO 70, DDO 75, DDO 155, and WLM. While most studies of dwarfs focus on bright systems or starbursts due to observational constraints, our data extend the observed parameter space into the regime of low surface brightness dwarf galaxies with low metallicities and moderate star formation rates. Our targets were observed with Herschel at the [CII] 158um, [OI] 63um, [OIII] 88um, and NII 122um emission lines using the PACS Spectrometer. These high-resolution maps allow us for the first time to study the far-infrared properties of these systems on the scales of larger star-forming complexes. The spatial resolution in our maps, in combination with star formation tracers, allows us to identify separate PDRs in some of the regions we observed. Our systems have widespread [CII] emission that is bright relative to continuum, averaging near 0.5% of the total infrared budget - higher than in solar-metallicity galaxies of other types. [NII] is weak, suggesting that the [CII] emission in our galaxies comes mostly from PDRs instead of the diffuse ionized ISM. These systems exhibit efficient cooling at low dust temperatures, as shown by ([OI]+[CII])/TIR in relation to 60um/100um, and low [OI]/[CII] ratios which indicate that [CII] is the dominant coolant of the ISM. We observe [OIII]/[CII] ratios in our galaxies that are lower than those published for other dwarfs, but similar to levels noted in spirals.

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arXiv2014

Spatially resolved physical conditions of molecular gas and potential star formation tracers in M83, revealed by the Herschel SPIRE FTS

Since the launch of the Herschel Space Observatory, our understanding about the photo-dissociation regions (PDR) has taken a step forward. In the bandwidth of the Fourier Transform Spectrometer (FTS) of the Spectral and Photometric Imaging REceiver (SPIRE) on board Herschel, ten CO rotational transitions, including J=4-3 to J=13-12, and three fine structure lines, including [CI] 609, [CI] 370, and [NII] 250 micron, are covered. In this paper, we present our findings from the FTS observations at the nuclear region of M83, based on the spatially resolved physical parameters derived from the CO spectral line energy distribution (SLED) map and the comparisons with the dust properties and star-formation tracers. We discuss (1) the potential of using [NII] 250 and [CI] 370 micron as star-formation tracers; (2) the reliability of tracing molecular gas with CO; (3) the excitation mechanisms of warm CO; (4) the possibility of studying stellar feedback by tracing the thermal pressure of molecular gas in the nuclear region of M83.

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arXiv2014

Molecular hydrogen emission in the interstellar medium of the Large Magellanic Cloud

We present the detection and analysis of molecular hydrogen emission toward ten interstellar regions in the Large Magellanic Cloud. We examined low-resolution infrared spectral maps of twelve regions obtained with the Spitzer infrared spectrograph (IRS). The pure rotational 0--0 transitions of H$_2$ at 28.2 and 17.1${\,\rm μm}$ are detected in the IRS spectra for ten regions. The higher level transitions are mostly upper limit measurements except for three regions, where a 3$σ$ detection threshold is achieved for lines at 12.2 and 8.6${\,\rm μm}$. The excitation diagrams of the detected H$_2$ transitions are used to determine the warm H$_2$ gas column density and temperature. The single-temperature fits through the lower transition lines give temperatures in the range $86-137\,{\rm K}$. The bulk of the excited H$_2$ gas is found at these temperatures and contributes $\sim$5-17% to the total gas mass. We find a tight correlation of the H$_2$ surface brightness with polycyclic aromatic hydrocarbon and total infrared emission, which is a clear indication of photo-electric heating in photodissociation regions. We find the excitation of H$_2$ by this process is equally efficient in both atomic and molecular dominated regions. We also present the correlation of the warm H$_2$ physical conditions with dust properties. The warm H$_2$ mass fraction and excitation temperature show positive correlations with the average starlight intensity, again supporting H$_2$ excitation in photodissociation regions.

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arXiv2014

The applicability of FIR fine-structure lines as Star Formation Rate tracers over wide ranges of metallicities and galaxy types

We analyze the applicability of far-infrared fine-structure lines [CII] 158 micron, [OI] 63 micron and [OIII] 88 micron to reliably trace the star formation rate (SFR) in a sample of low-metallicity dwarf galaxies from the Herschel Dwarf Galaxy Survey and compare with a broad sample of galaxies of various types and metallicities in the literature. We study the trends and scatter in the relation between the SFR (as traced by GALEX FUV and MIPS 24 micron) and far-infrared line emission, on spatially resolved and global galaxy scales, in dwarf galaxies. We assemble far-infrared line measurements from the literature and infer whether the far-infrared lines can probe the SFR (as traced by the total-infrared luminosity) in a variety of galaxy populations. In metal-poor dwarfs, the [OI] and [OIII] lines show the strongest correlation with the SFR with an uncertainty on the SFR estimates better than a factor of 2, while the link between [CII] emission and the SFR is more dispersed (uncertainty factor of 2.6). The increased scatter in the SFR-L([CII]) relation towards low metal abundances, warm dust temperatures, large filling factors of diffuse, highly ionized gas suggests that other cooling lines start to dominate depending on the density and ionization state of the gas. For the literature sample, we evaluate the correlations for a number of different galaxy populations. The [CII] and [OI] lines are considered to be reliable SFR tracers in starburst galaxies, recovering the star formation activity within an uncertainty of factor 2. [Abridged]

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