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-log(N/O) versus 12+log(He/H). Type I PNe and non-type I PNe are plotted as filled circles and empty circles respectively, according to the definition of Dopita (1991). The continuous line mark log(N/O)>-0.5 that, independently of helium abundance, defines the area of Type I PNe.
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![Fig. 4.-Same as Figure 3 but for the T e [N II] electron temperature....](profile/Laura-Magrini-2/publication/23787067/figure/fig3/AS:650515545325569@1532106400270/Same-as-Figure-3-but-for-the-T-e-N-II-electron-temperature-The-solid-line-represents_Q320.jpg)
The Planetary Nebula (PN) population of M33 is studied via multi-fiber
spectroscopy with Hectospec at the MMT. In this paper we present the spectra of
102 PNe, whereas plasma diagnostic and chemical abundances were performed on
the 93 PNe where the necessary diagnostic lines were measured. About 20% of the
PNe are compatible with being Type I; the...
Contexts in source publication
Context 1
... order to make a selection of the PNe with high-mass progenitors, in Figure 5, we plot the M33 disk PNe on the He-N/O plane. Peimbert & Torres-Peimbert (1983) found that Galactic PNe that were nitrogen-and helium-enriched also had bipolar shape, and were located closer to the Galactic plane. ...
Context 2
... cumulative sample of 89 H ii regions gives, Fig. 7.-The relationship between oxygen and sulphur abundances. Symbols are as in Figure 5. The continuous line is the weighted least square fit to the complete sample of PNe. ...
Context 3
... spec- troscopy performed to a set of 28 H ii regions. The cumulative sample of 89 H ii regions gives, Fig. 7.-The relationship between oxygen and sulphur abundances. Symbols are as in Figure 5. The continuous line is the weighted least square fit to the complete sample of PNe. Fig. 9.-The radial gradient of neon abundance. Symbols are as in Fig. 5. The continuous line is the weighted least square fit to the complete sample of disk PNe. Slopes and zero-points are shown in Table 6. Table 6. Note.-(1) The chemical element for which the gradient is computed; (2) slope of the abundance gradient; (3) zero-point (chemical abundances in the centre of the galaxy); (4) sample of PNe; (5) ...
Context 4
... For each element, the first row report the gradient obtained considering the whole sample of disk PNe (thus excluding the two possible halo PNe), the second row gives the gradient computed using non-Type I PNe, and the third row gives the gradient obtained of Type I PNe. Fig. 10.-The radial gradient of sulphur abun- dance. Symbols are as in Fig. 5. The continuous line is the weighted least square fit to the com- plete sample of disk PNe. Slopes and zero-points are shown in Table 6. (4) When compared to the best gradient deter- mined using M33 PNe (Eq. 3), we confirm that these gradients are consistent within the errors. We infer that the metallicity gradient of M33 has not ...
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Citations
... M33 is an obvious site to study HMXBs in the Local Group. It is the third largest spiral galaxy in the Local Group and has a measured metallicity gradient; the center of the galaxy is slightly supersolar, and the metallicity drops to roughly that of the LMC at the edges of the disk (Carrera et al. 2008;Cioni 2009;Magrini et al. 2009Magrini et al. , 2010Beasley et al. 2015;Toribio San Cipriano et al. 2016;Lin et al. 2017). Although it is about 10 times less massive than M31 or the Milky Way (e.g., Quirk et al. 2022), it has a higher SFR intensity (SFR per area; Verley et al. 2009;Lewis et al. 2015), making it an excellent site to study young stellar systems. ...
We present multiwavelength characterization of 65 high-mass X-ray binary (HMXB) candidates in M33. We use the Chandra ACIS survey of M33 (ChASeM33) catalog to select hard X-ray point sources that are spatially coincident with UV-bright point-source optical counterparts in the Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region catalog, which covers the inner disk of M33 at near-IR, optical, and near-UV wavelengths. We perform spectral energy distribution fitting on multiband photometry for each point-source optical counterpart to measure its physical properties including mass, temperature, luminosity, and radius. We find that the majority of the HMXB companion star candidates are likely B-type main-sequence stars, suggesting that the HMXB population of M33 is dominated by Be X-ray binaries (Be-XRBs), as is seen in other Local Group galaxies. We use spatially resolved recent star formation history maps of M33 to measure the age distribution of the HMXB candidate sample and the HMXB production rate for M33. We find a bimodal distribution for the HMXB production rate over the last 80 Myr, with a peak at ∼10 and ∼40 Myr, which match theoretical formation timescales for the most massive HMXBs and Be-XRBs, respectively. We measure an HMXB production rate of 107–136 HMXBs/( M ⊙ yr ⁻¹ ) over the last 50 Myr and 150–199 HMXBs/( M ⊙ yr ⁻¹ ) over the last 80 Myr. For sources with compact object classifications from overlapping NuSTAR observations, we find a preference for giant/supergiant companion stars in black hole HMXBs and main-sequence companion stars in neutron star HMXBs.
... Since then, it has been extensively studied, and is still a crucial object for the distance scale (Freedman et al. 1991;Lee et al. 2022): M33 has intermediate inclination (i = 57°± 4°; Kourkchi et al. 2020), 7 which limits the effects of reddening and of geometry that can produce additional scatter in the PL relation. Additionally, M33 is known for its steep metallicity gradient, which was measured using red giant branch (RGB) stars (Tiede et al. 2004), planetary nebulae (Magrini et al. 2009), and H II regions (Bresolin 2011;Toribio San Cipriano et al. 2016;Rogers et al. 2022). ...
We present a low-dispersion period–luminosity relation (PL) based on 154 Cepheids in Messier 33 (M33) with Hubble Space Telescope (HST) photometry from the PHATTER survey. Using high-quality ground-based light curves, we recover Cepheid phases and amplitudes for multi-epoch HST data and we perform template fitting to derive intensity-averaged mean magnitudes. HST observations in the SH0ES near-infrared Wesenheit system significantly reduce the effect of crowding relative to ground-based data, as seen in the final PL scatter of σ = 0.11 mag. We adopt the absolute calibration of the PL based on HST observations in the Large Magellanic Cloud and a distance derived using late-type detached eclipsing binaries to obtain a distance modulus for M33 of μ = 24.622 ± 0.030 mag ( d = 840 ± 11 kpc), a best-to-date precision of 1.3%. We find very good agreement with past Cepheid-based measurements. Several tip of the red giant branch estimates bracket our result while disagreeing with each other. Finally, we show that the flux contribution from star clusters hosting Cepheids in M33 does not impact the distance measurement and we find only ∼3.7% of the sample is located in (or nearby) young clusters. M33 offers one of the best sites for the cross-calibration of many primary distance indicators. Thus, a precise independent geometric determination of its distance would provide a valuable new anchor to measure the Hubble constant.
... M33 is an obvious site to study HMXBs in the Local Group. It is the third largest spiral galaxy in the Local Group and has a measured metallicity gradient; the center of the galaxy is slightly super-solar and the metallicity drops to roughly that of the LMC at the edges of the disk (Carrera et al. 2008;Cioni 2009;Magrini et al. 2009Magrini et al. , 2010Beasley et al. 2015;Toribio San Cipriano et al. 2016;Lin et al. 2017). Although it is about ten times less massive than M31 or the Milky Way (e.g., Quirk et al. 2022), it has a higher SFR intensity (SFR per area; Verley et al. 2009;Lewis et al. 2015), making it an excellent site to study young stellar systems. ...
We present multi-wavelength characterization of 65 high mass X-ray binary (HMXB) candidates in M33. We use the Chandra ACIS survey of M33 (ChASeM33) catalog to select hard X-ray point sources that are spatially coincident with UV-bright point source optical counterparts in the Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER) catalog, which covers the inner disk of M33 at near infrared, optical, and near ultraviolet wavelengths. We perform spectral energy distribution (SED) fitting on multi-band photometry for each point source optical counterpart to measure its physical properties including mass, temperature, luminosity, and radius. We find that the majority of the HMXB companion star candidates are likely B-type main sequence stars, suggesting that the HMXB population of M33 is dominated by Be-XRBs, as is seen in other Local Group galaxies. We use spatially-resolved recent star formation history (SFH) maps of M33 to measure the age distribution of the HMXB candidate sample and the HMXB production rate for M33. We find a bimodal distribution for the HMXB production rate over the last 80 Myr, with a peak at $\sim$10 Myr and $\sim$40 Myr, which match theoretical formation timescales for the most massive HMXBs and Be X-ray binaries (Be-XRBs), respectively. We measure an HMXB production rate of 107$-$136 HMXBs/(M$_{\odot}$ yr$^{-1}$) over the last 50 Myr and 150$-$199 HMXBs/(M$_{\odot}$ yr$^{-1}$) over the last 80 Myr. For sources with compact object classifications from overlapping NuSTAR observations, we find a preference for giant/supergiant companion stars in BH-HMXBs and main sequence companion stars in neutron star HMXBs (NS-HMXBs).
... The SFR intensity of M33 is higher than M31 (Verley et al. 2009;Lewis et al. 2015), allowing us to study high-intensity star formation regions. M33 also has well-known stellar and gasphase metallicity gradients (Cioni 2009;Magrini et al. 2009Magrini et al. , 2010Beasley et al. 2015;Toribio San Cipriano et al. 2016;Lin et al. 2017), which are similar to the Large Magellanic Cloud (LMC; Carrera et al. 2008). Unlike M31, M33 has likely not undergone a recent significant merger event, though recent spectroscopic observations may hint at a centrally concentrated population of accreted stars (Gilbert et al. 2022). ...
... While age-metallicity degeneracy is not as strong for main-sequence stars, the metallicity will strongly effect the color of the main sequence (e.g., Gallart et al. 2005). M33 has a well-established stellar and gas-phase metallicity gradient (Cioni 2009;Magrini et al. 2009Magrini et al. , 2010Toribio San Cipriano et al. 2016;Lin et al. 2017), and we explore the effects of metallicity on our results in Section 4.4. ...
We measure the spatially resolved recent star formation history (SFH) of M33 using optical images taken with the Hubble Space Telescope as part of the Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER) survey. The area covered by the observations used in this analysis covers a de-projected area of ∼38 kpc ² and extends to ∼3.5 and ∼2 kpc from the center of M33 along the major and semimajor axes, respectively. We divide the PHATTER optical survey into 2005 regions that measure 24 arcsec, ∼100 pc, on a side and fit color–magnitude diagrams for each region individually to measure the spatially resolved SFH of M33 within the PHATTER footprint. There are significant fluctuations in the SFH on small spatial scales and also galaxy-wide scales that we measure back to about 630 Myr ago. We observe a more flocculent spiral structure in stellar populations younger than about 80 Myr, while the structure of the older stellar populations is dominated by two spiral arms. We also observe a bar in the center of M33, which dominates at ages older than about 80 Myr. Finally, we find that the mean star formation rate (SFR) over the last 100 Myr within the PHATTER footprint is 0.32 ± 0.02 M ⊙ yr ⁻¹ . We measure a current SFR (over the last 10 Myr) of 0.20 ± 0.03 M ⊙ yr ⁻¹ . This SFR is slightly higher than previous measurements from broadband estimates, when scaled to account for the fraction of the D25 area covered by the PHATTER survey footprint.
... The star formation rate intensity of M33 is higher than M31 (Verley et al. 2009;Lewis et al. 2015), allowing us to study high intensity star formation regions. M33 also has well known stellar and gas-phase metallicity gradients (Cioni 2009;Magrini et al. 2009Magrini et al. , 2010Beasley et al. 2015;Toribio San Cipriano et al. 2016;Lin et al. 2017), which are similar to the LMC (Carrera et al. 2008). Unlike M31, M33 has likely not undergone a recent significant merger event, though recent spectroscopic observations may hint at a centrallyconcentrated population of accreted stars (Gilbert et al. 2021). ...
... While age-metallicity degeneracy is not as strong for main sequence stars, the metallicity will strongly effect the color of the main sequence (e.g., Gallart et al. 2005). M33 has a well-established stellar and gas-phase metallicity gradient (Cioni 2009;Magrini et al. 2009Magrini et al. , 2010Toribio San Cipriano et al. 2016;Lin et al. 2017) and we explore the effects of metallicity on our results in Section 4.4. ...
We measure the spatially resolved recent star formation history (SFH) of M33 using optical images taken with the Hubble Space Telescope as part of the Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER) survey. The area covered by the observations used in this analysis covers a de-projected area of $\sim$38 kpc$^{2}$ and extends to $\sim$3.5 and $\sim$2 kpc from the center of M33 along the major and semi-major axes, respectively. We divide the PHATTER optical survey into 2005 regions that measure 24 arcsec, $\sim$100 pc, on a side and fit color magnitude diagrams for each region individually to measure the spatially resolved SFH of M33 within the PHATTER footprint. There are significant fluctuations in the SFH on small spatial scales and also galaxy-wide scales that we measure back to about 630 Myr ago. We observe a more flocculent spiral structure in stellar populations younger than about 80 Myr, while the structure of the older stellar populations is dominated by two spiral arms. We also observe a bar in the center of M33, which dominates at ages older than about 80 Myr. Finally, we find that the mean star formation rate (SFR) over the last 100 Myr within the PHATTER footprint is 0.32$\pm$0.02 M$_{\odot}$ yr$^{-1}$. We measure a current SFR (over the last 10 Myr) of 0.20$\pm$0.03 M$_{\odot}$ yr$^{-1}$. This SFR is slightly higher than previous measurements from broadband estimates, when scaled to account for the fraction of the D25 area covered by the PHATTER survey footprint.
... Measuring chemical composition and distances of galaxies is crucial for our understanding of galaxy formation and evolution and for constraining the cosmological parameters. Distances provide the basis for the determination of the Hubble constant and are essential to characterize galaxy mass, radii, and luminosities, whereas the distribution of chemical composition of stars and the interstellar medium across the galaxies reflects the signature of the complex dynamics of galaxy evolution, such as galaxy merging, gas infall, galactic winds, star formation history, and initial mass function, and serves as a valuable constraint for detailed chemical evolution modeling (Henry & Worthey 1999;Magrini et al. 2009;Kudritzki et al. 2015). ...
Low-resolution LAMOST and Keck spectra of blue supergiant stars distributed over the disks of the Local Group spiral galaxies M31 and M33 are analyzed to determine stellar effective temperatures, gravities, metallicities, and reddening. Logarithmic metallicities at the center of the galaxies (in solar units) of 0.30 ± 0.09 and 0.11 ± 0.04 and metallicity gradients of −0.37 ± 0.13 dex/ R 25 and −0.36 ± 0.16 dex/ R 25 are measured for M31 and M33, respectively. For M33 the 2D distribution of metallicity indicates a deviation from azimuthal symmetry with an off-center peak. The flux-weighted gravity−luminosity relationship (FGLR) of blue supergiant stars is used to determine a distance modulus of 24.51 ± 0.13 mag for M31 and 24.93 ± 0.07 mag for M33. For M31 the FGLR distance agrees well with other methods. For M33 the FGLR-based distance is larger than the distances from Cepheids studies, but it is in good agreement with work on eclipsing binaries, planetary nebulae, long-period variables, and the tip of the red giant branch.
... Measuring chemical composition and distances of galaxies is crucial for our understanding of galaxy formation and evolution and for constraining the cosmological parameters. Distances provide the basis for the determination of the Hubble constant and are essential to characterize galaxy mass, radii and luminosities, whereas the distribution of chemical composition of stars and the interstellar medium accross the galaxies reflects the signature of the complex dynamics of galaxy evolution, such as, galaxy merging, gas infall, galactic winds, star formation history, and initial mass function and serves as a valuable constraint for detailed chemical evolution modeling (Henry & Worthey 1999;Magrini et al. 2009;Kudritzki et al. 2015). ...
Low-resolution LAMOST and Keck spectra of blue supergiant stars distributed over the disks of the Local Group spiral galaxies M 31 and M 33 are analyzed to determine stellar effective temperatures, gravities, metallicities, and reddening. Logarithmic metallicities at the center of the galaxies (in solar units) of $0.30\pm0.09$ and $0.11\pm0.04$ and metallicity gradients of $-0.37\pm0.13$ dex/$R_{25}$ and $-0.36\pm0.16$ dex/$R_{25}$ are measured for M 31 and M 33, respectively. For M 33 the 2-dimensional distribution of metallicity indicates a deviation from azimutal symmetry with an off-centre peak. The flux-weighted gravity-luminosity relationship of blue supergiant stars is used to determine a distance modulus of 24.51$\pm$0.13 mag for M 31 and 24.93$\pm$0.07 mag for M 33. For M 31 the flux-weighted gravity--luminosity relationship (FGLR) distance agrees well with other methods. For M 33 the FGLR-based distance is larger than the distances from Cepheids studies but it is in good agreement with work on eclipsing binaries, planetary nebulae , long-period variables, and the tip of the red giant branch.
... There are many studies where metallicity gradients were derived from H II regions, PNe, and massive supergiant stars in M33, e.g., Monteverde et al. (1997), Urbaneja et al. (2005), Crockett et al. (2006Crockett et al. ( ), U et al. (2009, Magrini et al. (2009), Rosolowsky & Simon (2008), Magrini et al. (2010), Bresolin et al. (2010), Bresolin (2011), Toribio San Cipriano et al. (2016, Lin et al. (2017), and others. The best review of current observational knowledge concerning the abundances of the ionized gas (H II regions and PNe) in nearby galaxies, including M33, and how they inform us about the time evolution of metallicity gradients can be found in Bresolin (2015). ...
... The best review of current observational knowledge concerning the abundances of the ionized gas (H II regions and PNe) in nearby galaxies, including M33, and how they inform us about the time evolution of metallicity gradients can be found in Bresolin (2015). Magrini et al. (2009Magrini et al. ( , 2010 claimed that H II regions and PNe have oxygen gradients very close within the errors. Their result was confirmed by Bresolin et al. (2010), who found no significant oxygen abundance offset between PNe and H II regions at any given galactocentric distance despite their different age groups. ...
... Our results confirm the existence of the axisymmetric global metallicity distribution that is assumed in many previous studies (see, e.g., Monteverde et al. 1997;Urbaneja et al. 2005;Crockett et al. 2006;U et al. 2009;Magrini et al. 2009;Rosolowsky & Simon 2008;Magrini et al. 2010;Bresolin et al. 2010;Bresolin 2011;Toribio San Cipriano et al. 2016;Lin et al. 2017). ...
Morphological and chemical structures of M33 are investigated with LAMOST DR7 survey. Physical parameters, extinction, chemical composition of He, N, O, Ne, S, Cl, Ar (where available), and radial velocities were determined for 110 nebulae (95 H\ii\ regions and 15 PNe) in M33. Among them, 8 PNe and 55 H\ii\ regions in M33 are newly discovered. We obtained the following O abundance gradients: $-$0.199$_{-0.030}^{+0.030}$ dex $R_{25}^{-1}$ (based on 95 H\ii\ regions), $-$0.124$_{-0.036}^{+0.036}$ dex $R_{25}^{-1}$ (based on 93 H\ii\ regions), and $-$0.207$_{-0.174}^{+0.160}$ dex $R_{25}^{-1}$ (based on 21 H\ii\ region), utilizing abundances from N2 at O3N2 diagnostics and the $T_{\rm e}$-sensitive method, respectively. The He, N, Ne, S, and Ar gradients resulted in slopes of $-$0.179$_{-0.146}^{+0.145}$, $-$0.431$_{-0.281}^{+0.282}$, $-$0.171$_{-0.239}^{+0.234}$, $-$0.417$_{-0.182}^{+0.174}$, $-$0.340$_{-0.157}^{+0.156}$, respectively, utilizing abundances from the $T_{\rm e}$-sensitive method. Our results confirm the existence of negative axisymmetric global metallicity distribution that is assumed in the literature. We noticed one new WC star candidate and one transition WR WN/C candidate. The grand-design pattern of spiral structure of M33 is presented.
... As an additional test, in order to verify the higher Ne/H abundance in AGNs in comparison with values derived in star-forming regions, we estimate the total neon abundance (Ne/H) in the central parts of galaxies based on the extrapolation of the radial abundance gradients of this element, which is generally found in spiral galaxies (e.g. Willner & Nelson-Patel 2002;Crockett et al. 2006;Rosolowsky & Simon 2008;Magrini et al. 2009;Stanghellini et al. 2010). This procedure helps us to infer indirect and independent values of abundances in the nuclei of spiral galaxies (e.g. ...
For the first time, neon abundance has been derived in the narrow line region from a sample of Seyfert 2 nuclei. In view of this, we compiled from the literature fluxes of optical and infrared (IR) narrow emission lines for 35 Seyfert 2 nuclei in the local universe ($z \:\lesssim \:0.06$). The relative intensities of emission lines were used to derive the ionic and total neon and oxygen abundances through electron temperature estimations (Te-method). For the neon, abundance estimates were obtained by using both Te-method and IR-method. Based on photoionization model results, we found a lower electron temperature [$t_{\rm e}({\rm Ne\, {\rm \small III}})$] for the gas phase where the Ne2 + is located in comparison with t3 for the O2 + ion. We find that the differences (D) between Ne2 +/H+ ionic abundances calculated from IR-method and Te −method (assuming t3 in the Ne2 +/H+ derivation) are similar to the derivations in star-forming regions (SFs) and they are reduced by a mean factor of ∼3 when $t_{\rm e}({\rm Ne\, {\rm \small III}})$ is considered. We propose a semi-empirical Ionization Correction Factor (ICF) for the neon, based on [Ne ii]12.81$\rm{\mu m}$, [Ne iii]15.56$\rm{\mu m}$ and oxygen ionic abundance ratios. We find that the average Ne/H abundance for the Seyfert 2s sample is nearly 2 times higher than similar estimate for SFs. Finally, for the very high metallicity regime (i.e. [$\rm 12+log(O/H)\: \gtrsim \: 8.80$]) an increase in Ne/O with O/H is found, which likely indicates secondary stellar production for the neon.
... As an additional test, in order to verify the higher Ne/H abundance in AGNs in comparison with values derived in star-forming regions, we estimate the total neon abundance (Ne/H) in the central parts of galaxies based on the extrapolation of the radial abundance gradients of this element, which is generally found in spiral galaxies (e.g. Willner & Nelson-Patel 2002;Crockett et al. 2006;Rosolowsky & Simon 2008;Magrini et al. 2009;Stanghellini et al. 2010). This procedure helps us to infer indirect and independent values of abundances in the nuclei of spiral galaxies (e.g. ...
For the first time, neon abundance has been derived in the narrow line region from a sample of Seyfert~2 nuclei. In view of this, we compiled from the literature fluxes of optical and infrared (IR) narrow emission lines for 35 Seyfert 2 nuclei in the local universe ($z < 0.06$). The relative intensities of emission lines were used to derive the ionic and total neon and oxygen abundances through electron temperature estimations ($T_{e}$-method). For the neon, abundance estimates were obtained by using both $T_{e}$-method and IR-method. Based on photoionization model results, we found a lower electron temperature [$t_{e}([Ne III])$] for the gas phase where the Ne$^{2+}$ is located in comparison with $t_{3}$ for the O$^{2+}$ ion. We find that the differences (D) between Ne$^{2+}$/H$^{+}$ ionic abundances calculated from IR-method and $T_{e}-$method (assuming $t_{3}$ in the Ne$^{2+}$/H$^{+}$ derivation) are similar to the derivations in star-forming regions (SFs) and they are reduced by a mean factor of $\sim3$ when $t_{e}([Ne III])$ is considered. We propose a semi-empirical Ionization Correction Factor (ICF) for the neon, based on [Ne II]12.81$\mu$m, [\ion{Ne}{iii}]15.56$\mu$m and oxygen ionic abundance ratios. We find that the average Ne/H abundance for the Seyfert 2s sample is nearly 2 times higher than similar estimate for SFs. Finally, for the very high metallicity regime (i.e. [$12+log(O/H) > 8.80$]) an increase in Ne/O with O/H is found, which likely indicates secondary stellar production for the neon.
