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We present a method to characterize star-formation driven outflows from edge-on galaxies and apply this method to the metal-poor starburst galaxy, Mrk 1486. Our method uses the distribution of emission line flux (from H β and [O iii] 5007) to identify the location of the outflow and measure the extent above the disc, the opening angle, and the transverse kinematics. We show that this simple technique recovers a similar distribution of the outflow without requiring complex modelling of line-splitting or multi-Gaussian components, and is therefore applicable to lower spectral resolution data. In Mrk 1486 we observe an asymmetric outflow in both the location of the peak flux and total flux from each lobe. We estimate an opening angle of 17–37° depending on the method and assumptions adopted. Within the minor axis outflows, we estimate a total mass outflow rate of ∼2.5 M⊙ yr−1, which corresponds to a mass loading factor of η = 0.7. We observe a non-negligible amount of flux from ionized gas outflowing along the edge of the disc (perpendicular to the biconical components), with a mass outflow rate ∼0.9 M⊙ yr−1. Our results are intended to demonstrate a method that can be applied to high-throughput low spectral resolution observations, such as narrow-band filters or low spectral resolution integral field spectrographs that may be more able to recover the faint emission from outflows.

 

Streams of intergalactic gas enriched by previous star formation were observed spiraling toward a massive galaxy. 

The hot component of the circumgalactic medium (CGM) around star-forming galaxies is detected as diffuse X-ray emission. The X-ray spectra from the CGM depend on the temperature and metallicity of the emitting plasma, providing important information about the feeding and feedback of the galaxy. The observed spectra are commonly fitted using simple one-temperature (1-T) or two-temperature (2-T) models. However, the actual temperature distribution of the gas can be complex because of the interaction between galactic outflows and halo gas. Here, we demonstrate this by analysing 3D hydrodynamical simulations of the CGM with a realistic outflow model. We investigate the physical properties of the simulated hot CGM, which shows a broad distribution in density, temperature, and metallicity. By constructing and fitting the simulated spectra, we show that, while the 1-T and 2-T models are able to fit the synthesized spectra reasonably well, the inferred temperature(s) does not bear much physical meaning. Instead, we propose a lognormal distribution as a more physical model. The lognormal model better fits the simulated spectra while reproducing the gas temperature distribution. We also show that when the star formation rate is high, the spectra inside the biconical outflows are distinct from those outside, as outflows are generally hotter and more metal enriched. Finally, we produce mock spectra for future missions with the eV-level spectral resolution, such as Athena, Lynx, the Hot Universe Baryon Surveyor, and theX-ray Imaging and Spectroscopy Mission.

 

We compare 500 pc scale, resolved observations of ionized and molecular gas for thez∼ 0.02 starbursting disk galaxy IRAS08339+6517, using measurements from KCWI and NOEMA. We explore the relationship of the star-formation-driven ionized gas outflows with colocated galaxy properties. We find a roughly linear relationship between the outflow mass flux (${\dot{\mathrm{\Sigma }}}_{\mathrm{out}}$) and star formation rate surface density (Σ_SFR),${\dot{\mathrm{\Sigma }}}_{\mathrm{out}}\propto {\mathrm{\Sigma }}_{\mathrm{SFR}}^{1.06\pm 0.10}$, and a strong correlation between${\dot{\mathrm{\Sigma }}}_{\mathrm{out}}$and the gas depletion time, such that${\dot{\mathrm{\Sigma }}}_{\mathrm{out}}\propto t_{\mathrm{dep}}^{-1.1\pm 0.06}$. Moreover, we find these outflows are so-calledbreakoutoutflows, according to the relationship between the gas fraction and disk kinematics. Assuming that ionized outflow mass scales with total outflow mass, our observations suggest that the regions of highest Σ_SFRin IRAS08 are removing more gas via the outflow than through the conversion of gas into stars. Our results are consistent with a picture in which the outflow limits the ability of a region of a disk to maintain short depletion times. Our results underline the need for resolved observations of outflows in more galaxies.

 

We study star formation-driven outflows in a z ∼ 0.02 starbursting disc galaxy, IRAS08339+6517, using spatially resolved measurements from the Keck Cosmic Web Imager (KCWI). We develop a new method incorporating a multistep process to determine whether an outflow should be fit in each spaxel, and then subsequently decompose the emission line into multiple components. We detect outflows ranging in velocity, vout, from 100 to 600 km s−1 across a range of star formation rate surface densities, ΣSFR, from ∼0.01 to 10 M⊙ yr−1 kpc−2 in resolution elements of a few hundred parsec. Outflows are detected in ∼100 per cent of all spaxels within the half-light radius, and ∼70 per cent within r90, suggestive of a high covering fraction for this starbursting disc galaxy. Around 2/3 of the total outflowing mass originates from the star forming ring, which corresponds to ${\lt}10{{\ \rm per\ cent}}$ of the total area of the galaxy. We find that the relationship between vout and the ΣSFR, as well as between the mass loading factor, η, and the ΣSFR, are consistent with trends expected from energy-driven feedback models. We study the resolution effects on this relationship and find stronger correlations above a re-binned size-scale of ∼500 pc. Conversely, we do not find statistically significant consistency with the prediction from momentum-driven winds.

 

In recent years, organic dye molecules as photosensitizers have played a significant role in the field of dye-sensitized solar cells. In this context, two primary dihydroindolocarbazole-based organic dyes (sk201 and sk202), which were synthesized recently by Song et al., and three further designed dyes (DMZ1-3) were theoretically investigated based on density functional theory and time-dependent density functional theory. Molecular geometries, absorption spectra, charge transfer, molecular electrostatic potential and nonlinear optical properties were quantificationally studied and visually presented to reveal the relationships between the molecular structures and performances of dyes. The effects of joining the isolated dyes and TiO2 on the molecular absorption spectra and energy levels were analyzed. Moreover, several parameters, such as efficiency of light-harvesting, driving forces of electron regeneration and injection, excited-state lifetime and vertical dipole moment, were calculated to give the multi-angle demonstrations of the photovoltaic performances for these dyes. 

Cell membrane coating has recently emerged as a promising biomimetic approach to engineering nanoparticles (NPs) for targeted drug delivery. However, simple cell membrane coating may not meet the need for efficient drug delivery to the brain. Here, a novel molecular engineering strategy to modify the surface of NPs with a cell membrane coating for enhanced brain penetration is reported. By using poly(lactic‐co‐glycolic) acid NPs as a model, it is shown that delivery of NPs to the ischemic brain is enhanced through surface coating with the membrane of neural stem cells (NSCs), and the delivery efficiency can be further increased using membrane isolated from NSCs engineered for overexpression of CXCR4. It is found that this enhancement is mediated by the chemotactic interaction of CXCR4 with SDF‐1, which is enriched in the ischemic microenvironment. It is demonstrated that the resulting CXCR4‐overexpressing membrane‐coated NPs, termed CMNPs, significantly augment the efficacy of glyburide, an anti‐edema agent, for stroke treatment. The study suggests a new approach to improving drug delivery to the ischemic brain and establishes a novel formulation of glyburide that can be potentially translated into clinical applications to improve management of human patients with stroke.