Intra-night multiband light curves of MAGIC J2001+439 observations on 2010 July 16. Top panel: VHE gamma-ray flux above 200 GeV, as measured by MAGIC. The open circles depict the fluxes with excess significances between 0 and 1.2σ (calculated according to Li & Ma 1983, Eq. (17)). The gray arrows report the 95% confidence level upper limits. The magenta solid line depicts 10% of the Crab Nebula flux, while the red dashed line reports the result of a fit with a constant function (χ²/n_d.o.f. = 9.3/4). Middle panel: X-ray count rate in the energy range 0.3–10 keV, as measured by Swift XRT. The blue dashed line depicts the result of a fit with a constant function (χ²/n_d.o.f. = 12.3/11). Bottom panel: hardness ratio (2–10 keV)/(0.3–2 keV). The black dashed line depicts the result of a fit with a constant function (χ²/n_d.o.f. = 2.9/2). The X-ray count rate and hardness ratios were extracted from the automatic Swift XRT analysis for LAT sources⁶.