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BACKGROUND Procrastination is the unnecessary delay of a task that subsequently creates anxiety (Rothblum, Solomon, & Maurakami, 1986). Research suggests that procrastination is linked with poorer mental health, but questions remain regarding its association with anxiety disorders. Studies exploring obsessive-compulsive disorder (OCD) and procrastination have found high levels of procrastination in OCD (Ferrari & McCown, 1994), but have also found no association between obsessive thoughts and procrastination (Kağan, Çakır, İlhan, & Kandemir, 2010). Scher and Osterman (2002) found that procrastination correlated with physiological anxiety and social anxiety, but not worry. No previous research has examined the connection between procrastination and health anxiety. PARTICIPANTS AND PROCEDURE A non-clinical university sample (N = 300) completed online self-report questionnaires in order to examine the relationships between procrastination and symptoms of OCD, generalised anxiety disorder, social anxiety disorder, health anxiety, and panic disorder. RESULTS Symptoms of panic disorder, social anxiety disorder, and health anxiety correlated with levels of procrastination. However, using a multiple regression analysis, only panic disorder symptoms uniquely predicted procrastination. CONCLUSIONS It is proposed that people with panic disorder may procrastinate to avoid anxiety inducing situations, or that individuals who frequently procrastinate may become sensitive to the anxiety caused by procrastination, thereby potentially triggering panic disorder. The full implications of these findings are further discussed. [ABSTRACT FROM AUTHOR]

Spectroscopic studies of extreme-ionization galaxies (EIGs) are critical to our understanding of exotic systems throughout cosmic time. These EIGs exhibit spectral features requiring >54.42 eV photons: the energy needed to ionize helium into He2+ fully and emit He ii recombination lines. Spectroscopic studies of EIGs can probe exotic stellar populations or accretion onto intermediate-mass black holes (∼102–105 M ⊙), which are the possibly key contributors to the reionization of the Universe. To facilitate the use of EIGs as probes of high-ionization systems, we focus on ratios constructed from several rest-frame UV/optical emission lines: [O iii ] λ 5008, H β, [Ne iii ] λ 3870, [O ii ] λ λ 3727, 3729, and [Ne v ] λ 3427. These lines probe the relative intensity at energies of 35.12, 13.62, 40.96, 13.62, and 97.12 eV, respectively, covering a wider range of ionization than traced by other common rest-frame UV/optical techniques. We use the ratios of these lines ([Ne v ]/[Ne iii ] ≡ Ne53, [O iii ]/H β, and [Ne iii ]/[O ii ]), which are nearby in wavelength, mitigating the effects of dust attenuation and uncertainties in flux calibration. We make predictions from photoionization models constructed from Cloudy that use a broad range of stellar populations and black hole accretion models to explore the sensitivity of these line ratios to changes in the ionizing spectrum. We compare our models to observations from the Hubble Space Telescope and JWST of galaxies with strong high-ionization emission lines at z ∼ 0, z ∼ 2, and 5 < z < 8.5. We show that the Ne53 ratio can separate galaxies with ionization from "normal" stellar populations from those with active galactic nuclei and even "exotic" Population III models. We introduce new selection methods to identify galaxies with photoionization driven by Population III stars or intermediate-mass black hole accretion disks that could be identified in upcoming high-redshift spectroscopic surveys. [ABSTRACT FROM AUTHOR]

We present the results from a spectroscopic survey using the MOSFIRE near-infrared spectrograph on the 10 m Keck telescope to search for Ly α emission from candidate galaxies at z ∼ 9â€"10 in four of the CANDELS fields (GOODS-N, EGS, UDS, and COSMOS). We observed 11 target galaxies, detecting Ly α from one object in ∼8.1 hr of integration, at z = 8.665 ± 0.001 with an integrated signal-to-noise ratio > 7. This galaxy is in the CANDELS Extended Groth Strip (EGS) field and lies physically close (3.5 physical Mpc [pMpc]) to another confirmed galaxy in this field with Ly α detected at z = 8.683. The detection of Ly α suggests the existence of large (∼1 pMpc) ionized bubbles fairly early in the reionization process. We explore the ionizing output needed to create bubbles of this size at this epoch and find that such a bubble requires more than the ionizing power provided by the full expected population of galaxies (by integrating the UV luminosity function down to M UV = âˆ'13). The Ly α we detect would be able to escape the predominantly neutral intergalactic medium at this epoch if our detected galaxy is inhabiting an overdensity, which would be consistent with the photometric overdensity previously identified in this region by Finkelstein et al. This implies that the CANDELS EGS field is hosting an overdensity at z = 8.7 that is powering one or more ionized bubbles, a hypothesis that will be imminently testable with forthcoming James Webb Space Telescope observations in this field. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV; rest-frame ∼1200–2000 Å) spectra provide a wealth of diagnostics to characterize fundamental galaxy properties, such as their chemical enrichment, the nature of their stellar populations, and their amount of Lyman-continuum (LyC) radiation. In this work, we leverage publicly released JWST data to construct the rest-frame UV-to-optical composite spectrum of a sample of 63 galaxies at 5.6 < z < 9, spanning a wavelength range from 1500 to 5200 Å. Based on the composite spectrum, we derive an average dust attenuation E (B − V) gas = 0.10 − 0.11 + 0.10 from H β /H γ, an electron density n e = 570 − 290 + 510 cm−3 from the [O ii ] doublet ratio, an electron temperature T e = 16700 − 1500 + 1500 K from the [O iii ] λ 4363/[O iii ] λ 5007 ratio, and an ionization parameter log (U) = − 2.15 − 0.03 + 0.03 from the [O iii ]/[O ii ] ratio. Using a direct T e method, we calculate an oxygen abundance 12 + log (O / H) = 7.67 ± 0.08 and a carbon-to-oxygen (C/O) abundance ratio log (C / O) = − 0.86 − 0.10 + 0.13 . This C/O ratio is smaller than compared to z = 0 and z = 2–4 star-forming galaxies, albeit with moderate significance. This indicates the reionization-era galaxies might be undergoing a rapid buildup of stellar mass with high specific star formation rates. A UV diagnostic based on the ratios of C iii ] λ λ 1907, 1909/He ii λ 1640 versus O iii ] λ 1666/He ii λ 1640 suggests that the star formation is the dominant source of ionization, similar to the local extreme dwarf galaxies and z ∼ 2–4 He ii –detected galaxies. The [O iii ]/[O ii ] and C iv /C iii ] ratios of the composite spectrum are marginally larger than the criteria used to select galaxies as LyC leakers, suggesting that some of the galaxies in our sample are strong contributors to the reionizing radiation. [ABSTRACT FROM AUTHOR]

We present JWST and Atacama Large Millimeter/submillimeter Array (ALMA) imaging for the lensing system SPT0418−47, which includes a strongly lensed, dusty, star-forming galaxy at redshift z = 4.225 and an associated multiply imaged companion. The JWST NIRCam and MIRI imaging observations presented in this paper were acquired as part of the Early Release Science program Targeting Extremely Magnified Panchromatic Lensed Arcs and Their Extended Star formation (TEMPLATES). This data set provides robust mutiwavelength detections of stellar light in both the main (SPT0418A) and companion (SPT0418B) galaxies, while the ALMA detection of [C ii ] emission confirms that SPT0418B lies at the same redshift as SPT0418A. We infer that the projected physical separation of the two galaxies is 4.42 ± 0.05 kpc. We derive total magnifications of μ = 29 ± 1 and μ = 4.1 ± 0.7 for SPT0418A and SPT0418B, respectively. We use both prospector and cigale to derive stellar masses. We find that SPT0418A has a stellar mass of M * = 3.4 − 0.6 + 1.1 × 10 10 M ⊙ from prospector or M * = 1.5 ± 0.3 × 1010 M ⊙ from cigale. The stellar mass ratio of SPT0418A and SPT0418B is roughly between 4 and 7 ( 4.2 − 1.6 + 1.9 for prospector and 7.5 ± 3.7 for cigale). We see evidence of extended structure associated with SPT0418A that is suggestive of a tidal feature. These features, along with the close projected proximity, imply that the system is interacting. Interestingly, the star formation rates and stellar masses of both galaxies are consistent with the main sequence of star-forming galaxies at this epoch, indicating that this ongoing interaction has not noticeably elevated the star formation levels. [ABSTRACT FROM AUTHOR]

We report the discovery of four galaxy candidates observed 450–600 Myr after the Big Bang with photometric redshifts between z ∼ 8.3 and 10.2 measured using James Webb Space Telescope (JWST) NIRCam imaging of the galaxy cluster WHL0137−08 observed in eight filters spanning 0.8–5.0 μ m, plus nine Hubble Space Telescope filters spanning 0.4–1.7 μ m. One candidate is gravitationally lensed with a magnification of μ ∼ 8, while the other three are located in a nearby NIRCam module with expected magnifications of μ ≲ 1.1. Using SED fitting, we estimate the stellar masses of these galaxies are typically in the range log M ⋆ / M ⊙ = 8.3–8.7. All appear young, with mass-weighted ages <240 Myr, low dust content A V < 0.15 mag, and specific star formation rates sSFR ∼0.25–10 Gyr−1 for most. One z ∼ 9 candidate is consistent with an age <5 Myr and an sSFR ∼10 Gyr−1, as inferred from a strong F444W excess, implying [O iii ]+H β rest-frame equivalent width ∼2000 Å, although an older z ∼ 10 object is also allowed. Another z ∼ 9 candidate is lensed into an arc 2.″4 long with a magnification of μ ∼ 8. This arc is the most spatially resolved galaxy at z ∼ 9 known to date, revealing structures ∼30 pc across. Follow-up spectroscopy of WHL0137−08 with JWST/NIRSpec will be useful to spectroscopically confirm these high-redshift galaxy candidates and to study their physical properties in more detail. [ABSTRACT FROM AUTHOR]

We present the first JWST observations of the z  = 4.11 luminous radio galaxy TN J1338–1942, obtained as part of the 'Prime Extragalactic Areas for Reionization and Lensing Science' ('PEARLS') project. Our NIRCam observations, designed to probe the key rest-frame optical continuum and emission line features at this redshift, enable resolved spectral energy distribution modelling that incorporates both a range of stellar population assumptions and radiative shock models. With an estimated stellar mass of log10(M /M⊙) ∼ 10.9, TN J1338–1942 is confirmed to be one of the most massive galaxies known at this epoch. Our observations also reveal extremely high equivalent-width nebular emission coincident with the luminous AGN jets that is best fit by radiative shocks surrounded by extensive recent star formation. We estimate the total star-formation rate (SFR) could be as high as |$\sim 1600\, \text{M}_{\odot }\, \text{yr}^{-1}$| , with the SFR that we attribute to the jet induced burst conservatively |$\gtrsim 500\, \text{M}_{\odot }\, \text{yr}^{-1}$|. The mass-weighted age of the star-formation, t mass < 4 Myr, is consistent with the likely age of the jets responsible for the triggered activity and significantly younger than that measured in the core of the host galaxy. The extreme scale of the potential jet-triggered star-formation activity indicates the potential importance of positive AGN feedback in the earliest stages of massive galaxy formation, with our observations also illustrating the extraordinary prospects for detailed studies of high-redshift galaxies with JWST. [ABSTRACT FROM AUTHOR]

We analyze a sample of 25 [Ne v ] (λ 3426) emission-line galaxies at 1.4 < z < 2.3 using Hubble Space Telescope/Wide Field Camera 3 G102 and G141 grism observations from the CANDELS Ly α Emission at Reionization (CLEAR) survey. [Ne v ] emission probes extremely energetic photoionization (creation potential of 97.11 eV) and is often attributed to energetic radiation from active galactic nuclei (AGNs), shocks from supernovae, or an otherwise very hard ionizing spectrum from the stellar continuum. In this work, we use [Ne v ] in conjunction with other rest-frame UV/optical emission lines ([O ii ] λ λ 3726, 3729, [Ne iii ] λ 3869, H β, [O iii ] λ λ 4959, 5007, H α +[N ii ] λ λ 6548, 6583, [S ii ] λ λ 6716, 6731), deep (2–7 Ms) X-ray observations (from Chandra), and mid-infrared imaging (from Spitzer) to study the origin of this emission and to place constraints on the nature of the ionizing engine. The majority of the [Ne v ]-detected galaxies have properties consistent with ionization from AGNs. However, for our [Ne v ]-selected sample, the X-ray luminosities are consistent with local (z ≲ 0.1) X-ray-selected Seyferts, but the [Ne v ] luminosities are more consistent with those from z ∼ 1 X-ray-selected QSOs. The excess [Ne v ] emission requires either reduced hard X-rays or a ∼0.1 keV excess. We discuss possible origins of the apparent [Ne v ] excess, which could be related to the "soft (X-ray) excess" observed in some QSOs and Seyferts and/or be a consequence of a complex/anisotropic geometry for the narrow-line region, combined with absorption from a warm, relativistic wind ejected from the accretion disk. We also consider implications for future studies of extreme high-ionization systems in the epoch of reionization (z ≳ 6) with the James Webb Space Telescope. [ABSTRACT FROM AUTHOR]

We present a detailed stellar population analysis of 11 bright (H < 26.6) galaxies at z = 9â€"11 (three spectroscopically confirmed) to constrain the chemical enrichment and growth of stellar mass of early galaxies. We use the flexible Bayesian spectral energy distribution (SED) fitting code Prospector with a range of star formation histories (SFHs), a flexible dust attenuation law, and a self-consistent model of emission lines. This approach allows us to assess how different priors affect our results and how well we can break degeneracies between dust attenuation, stellar ages, metallicity, and emission lines using data that probe only the rest-frame ultraviolet (UV) to optical wavelengths. We measure a median observed UV spectral slope β = âˆ' 1.87 âˆ' 0.43 + 0.35 for relatively massive star-forming galaxies ( 9 < log (M ⋆ / M ⊙) < 10), consistent with no change from z = 4 to z = 9â€"10 at these stellar masses, implying rapid enrichment. Our SED-fitting results are consistent with a star-forming main sequence with sublinear slope (0.7 ± 0.2) and specific star formation rates of 3â€"10 Gyrâˆ'1. However, the stellar ages and SFHs are less well constrained. Using different SFH priors, we cannot distinguish between median mass-weighted ages of ∼ 50â€"150 Myr, which corresponds to 50% formation redshifts of z 50 ∼ 10â€"12 at z ∼ 9 and is of the order of the dynamical timescales of these systems. Importantly, models with different SFH priors are able to fit the data equally well. We conclude that the current observational data cannot tightly constrain the mass-buildup timescales of these z = 9â€"11 galaxies, with our results consistent with SFHs implying both a shallow and steep increase in the cosmic SFR density with time at z > 10. [ABSTRACT FROM AUTHOR]

Lyα emission from galaxies can be utilized to characterize the ionization state in the intergalactic medium (IGM). We report our search for Lyα emission at z > 7 using a comprehensive Keck/MOSFIRE near-infrared spectroscopic data set, as part of the Texas Spectroscopic Search for Lyα Emission at the End of Reionization Survey. We analyze data from 10 nights of MOSFIRE observations which together target 72 high-z candidate galaxies in the GOODS-N field, all with deep exposure times of 4.5–19 hr. Utilizing an improved automated emission-line search, we report 10 Lyα emission lines detected (>4σ) at z > 7, significantly increasing the spectroscopically confirmed sample. Our sample includes large equivalent-width (EW) Lyα emitters (>50 Å), and additional tentative Lyα emission lines detected at 3σ–4σ from five additional galaxies. We constrain the Lyα EW distribution at z ∼ 7.6, finding a significant drop from z ≲ 6, suggesting an increasing fraction of neutral hydrogen (H i) in the IGM in this epoch. We estimate the Lyα transmission through the IGM (=EWz ∼ 7.6/EW) and infer an IGM H i fraction (XHI) of at z ∼ 7.6, which is lower in modest tension (>1σ) with recent measurements at z ∼ 7.6. The spatial distribution of the detected Lyα emitters implies the presence of a potential highly ionized region at z ∼ 7.55, which hosts four Lyα emitters within a ∼40 cMpc spatial separation. The prominence of this ionized region in our data set could explain our lower inferred value of XHI, though our analysis is also sensitive to the chosen reference Lyα EW distribution values and reionization models. [ABSTRACT FROM AUTHOR]