All Figures

Figure 1: XMM-Newton/EPIC image of the region surrounding McNeil's Nebula. The three images obtained with PN, MOS1, and MOS2 EPIC cameras on 2004 April 4 were added after correction from vignetting. The size of the image pixel is 3 . This image has red, green, and blue colour coding for X-ray photons in the 0.5-1.5, 1.5-2.4, and 2.4-8.0 keV energy bands, respectively (see algorithm of Lupton et al. 2004). For comparison purposes we overlay a R-band contour map of the nebula obtained with VLT/FORS2 on 2004 February 18. X-ray sources and 2MASS sources are marked with "'' and "+'' respectively. A bright embedded X-ray source is spatially coincident with V1647 Ori at the apex of McNeil's nebula.

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In the text

Figure 2: XMM-Newton/EPIC background subtracted X-ray light curves of V1647 Ori. The upper panel shows the EPIC (PN+MOS1+MOS2) X-ray light curve of V1647 Ori with one sigma error bars in the energy band from 0.5 to 8.0 keV. The grey stripes indicate the small observational time intervals before the start and the end of the PN exposure where only the two MOS detectors were observing. The middle panels show the soft ( S=0.5-2.8 keV) and hard (H=2.8-8 keV) band X-ray light curves. The lower panel shows the variation of the corresponding hardness ratio. The dashed line indicates the hardness ratio for the second half of the observation.

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In the text

Figure 3: Comparison between the observed hardness ratios and absorbed one temperature plasma models. The left and right hand vertical grey stripes indicate the hardness ratio values of the first and the second halves of the observation, respectively, measured with EPIC (see lower panel of Fig. 2). The curves give plasma temperature versus hardness ratio for a fixed value of the hydrogen column density. The dashed areas show the constraints on the model parameters when combining the results from the quantile analysis of PN data (see lower panel of Fig. 4) with hardness ratios measured with EPIC.

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In the text

Figure 4: Quantile analysis of the energy of the X-ray photons of V1647 Ori collected by EPIC/PN. The upper panel shows the EPIC/PN light curve of V1647 Ori in the 0.5-8.0 keV energy band. Vertical dashed lines define variable-length time bins numbered from #1 to #5 where PN collected 200 net counts. For each time bin, the box plot indicates the energy distribution of the source (the vertical line and the box indicate the energy range and the quartiles/median, respectively) corrected from background (except minimum and maximum values) using the Hong et al. (2004) method. The grey box plot corresponding to bin #2-#5 indicates the energy distribution of the entire second half of the observation. The lower panel shows the X-ray colour-colour diagram based on median and the ratio of two quartiles (Hong et al. 2004). The numbered asterisks mark the X-ray colours corresponding to the time bins defined in the upper panel. The diamond marks the X-ray colours of the second half of the observation. Typical one sigma error bars are shown for comparison.

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In the text

Figure 5: XMM-Newton X-ray spectra and our best fit models of V1647 Ori. The upper panel shows the data binned to 15 counts in each spectral bin, and our best fit models with an absorbed two-temperature optically thin plasma (see model #2 in Table 1). Continuous line, dashed line plus squares, and dotted line plus disks, stand for PN, MOS1, and MOS2, respectively. The lower panel shows the residuals of the fit, in units of the uncertainties in the individual data points. The Fe  XXV emission line at 6.7 keV is clearly visible.

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In the text

	Figure 6: Fit around the 6.7 keV iron line region. The left hand panel shows an enlargement of the absorbed two-temperature model (see model 2 in Table 1) around the 6.7 keV iron line, using a linear energy scale. The right hand panel shows the same energy area adding a Gaussian line fitting the 6.4 keV neutral iron line (see model 3 in Table 1). Symbols are identical to the ones of Fig. 5.
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In the text

Figure 7: Long term multiwavelength variation of the observed flux density of V1647 Ori. The left hand panel (adapted from Kastner et al. 2004) shows the variation of the observed flux density of V1647 Ori from the optical (I band), near-IR (J, H, and K bands), and X-ray (0.5-8 keV energy band). The first three X-ray measurements are from  Chandra (Kastner et al. 2004), where we have computed for the 2002 November 14 measurement the 90% confidence level from observed counts using Gehrels (1986) statistics. The dotted arrow marks the X-ray upper limit at the 90% confidence level computed from the XMM-Newton observation of HH24-26 on 2003 September 3 (Ozawa et al., in preparation). The range of X-ray flux density that we report here with XMM-Newton is represented by a segment, detailed in the right hand panel. The right hand panel shows the X-ray flux density observed with XMM-Newton, computed from the EPIC light curve (upper panel of Fig. 2) using a conversion factor from count rate to flux density derived from our best spectral fit (Fig. 5). One sigma error bars are given for both XMM-Newton and Chandra fluxes.

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In the text

Figure 8: Folded XMM-Newton and Chandra X-ray fluxes of V1647 Ori. The left hand panel plots the function versus trial period, from the value given by the length of the XMM-Newton observation to 2.3 days with period step of 10-6 s. This function is defined only for periods allowing the folding of the two Chandra measurements with the XMM-Newton light curve (see text for details). Diamonds mark the best three shortest trial periods with their corresponding -harmonic. The right hand panel displays the resulting XMM-Newton (line) and Chandra (grey hourglasses)  flux measurements folded using these three periods. The error bars represent the equivalent XMM-Newton flux integrated during the Chandra observing time. The last plot of the right hand panel shows for comparison a bad fit corresponding to the point marked by an asterisk in the left hand panel.

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In the text